Dynamically rigidizing composite medical structures

ABSTRACT

A rigidizing device includes an elongate flexible tube, a braid layer positioned over the elongate flexible tube, an outer layer over the flexible tube and the braid layer, and an inlet between the elongate flexible tube and the outer layer and configured to attach to a source of vacuum or pressure. The braid layer has a plurality of strands braided together at a braid angle of 5-40 degrees relative to a longitudinal axis of the elongate flexible tube when the elongate flexible tube is straight. The rigidizing device is configured to have a rigid configuration when vacuum or pressure is applied through the inlet and a flexible configuration when vacuum or pressure is not applied through the inlet. The braid angle is configured to change as the rigidizing device bends when the rigidizing device is in the flexible configuration.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/US2019/042650, filed Jul. 19, 2019, titled “DYNAMICALLY RIGIDIZINGCOMPOSITE MEDICAL STRUCTURES,” which claims priority to U.S. ProvisionalApplication No. 62/835,101, filed Apr. 17, 2019, titled “DYNAMICALLYRIGIDIZING COMPOSITE MEDICAL STRUCTURES,” U.S. Provisional ApplicationNo. 62/854,199, filed May 29, 2019, titled “DYNAMICALLY RIGIDIZINGCOMPOSITE MEDICAL STRUCTURES,” U.S. Provisional Application No.62/780,820, filed Dec. 17, 2018, titled “DYNAMICALLY RIGIDIZINGCOMPOSITE MEDICAL STRUCTURES,” and U.S. Provisional Patent ApplicationNo. 62/700,760, filed Jul. 19, 2018, titled “BRAIDED DYNAMICALLYRIGIDIZING OVERTUBE,” the entireties of which are incorporated byreference herein.

This application may also be related to International Patent ApplicationNo. PCT/US2018/042946, filed Jul. 19, 2018, titled “DYNAMICALLYRIGIDIZING OVERTUBE,” which claims priority to U.S. Provisional PatentApplication No. 62/672,444, filed May 16, 2018, titled “DYNAMICALLYRIGIDIZING OVERTUBE,” and U.S. Provisional Patent Application No.62/535,134, filed Jul. 20, 2017, titled “DYNAMICALLY RIGIDIZINGOVERTUBE,” the entireties of which are incorporated by reference herein.

This application may also be related to U.S. patent application Ser. No.15/757,230, filed Mar. 2, 2018, titled “DEVICE FOR ENDOSCOPICADVANCEMENT THROUGH THE SMALL INTESTINE,” now U.S. Patent ApplicationPublication No. US2018/0271354, which national phase application under35 USC 371 of International Patent Application No. PCT/US2016/050290,filed Sep. 2, 2016, titled “DEVICE FOR ENDOSCOPIC ADVANCEMENT THROUGHTHE SMALL INTESTINE,” now International Publication No. WO 2017/041052,which claims priority to U.S. Provisional Patent Application No.62/339,593, filed May 20, 2016, titled “DEVICE FOR ENDOSCOPISADVANCEMENT THROUGH THE SMALL INTESTINE,” and U.S. Provisional PatentApplication No. 62/213,908, filed Sep. 3, 2015, and titled “DEVICE FORENDOSCOPIC ADVANCEMENT THROUGH THE SMALL INTESTINE,” the entireties ofwhich are incorporated by reference herein.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

BACKGROUND

During medical procedures, the interventional medical device can curveor loop through the anatomy, making advancement of the medical devicedifficult.

Gastrointestinal looping, caused when the endoscope can no longeradvance due to excessive curving or looping of the gastrointestinaltract, is a particularly well-known clinical challenge for endoscopy.Indeed, one study found that looping occurred in 91 of 100 patientsundergoing colonoscopy [Shah et al, “Magnetic Imaging of Colonoscopy: AnAudit of Looping, Accuracy and Ancillary maneuvers.” Gastrointest Endosc2000; 52: 1-8]. Gastrointestinal looping prolongs the procedure and cancause pain to the patient because it can stretch the vessel wall and themesentery. Furthermore, gastrointestinal looping leads to an increasedincidence of perforations. In severe cases of gastrointestinal looping,complete colonoscopies are impossible since looping stretches the lengthof the colon and the colonoscope is not long enough to reach the end.Gastrointestinal looping is an impediment to precise tip control,denying the user the coveted one-to-one motion relationship between thehandle and the endoscope tip. Such problems commonly occur across a widerange of endoscopic procedures, including colonoscopy,esophagogastroduodenoscopy (EGD), enteroscopy, endoscopic retrogradecholangiopancreatography (ERCP), interventional endoscopy procedures(including ESD (Endoscopic Submucosal Dissection) and EMR (EndoscopicMucosal Resection)), robotic flexible endoscopy, trans-oral roboticsurgery (TORS), altered anatomy cases (including Roux-en-Y), and duringNOTES (Natural Orifice Transluminal Endoscopic Surgery) procedures.Accordingly, there is a need for device that helps preventgastrointestinal looping to provide more successful access to thegastrointestinal tract.

Similar difficulties in advancing medical instruments can arise, forexample, during interventional procedures in the lungs, kidneys, brain,cardiac space, and other anatomical locations. Accordingly, there is aneed for a device that can provide safe, efficient, and precise accessto otherwise difficult to reach anatomical locations.

SUMMARY OF THE DISCLOSURE

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a braid layer positioned over the elongate flexible tube,an outer layer over the flexible tube and the braid layer, and an inletbetween the elongate flexible tube and the outer layer and configured toattach to a source of vacuum or pressure. The braid layer has aplurality of strands braided together at a braid angle of 5-40 degreesrelative to a longitudinal axis of the elongate flexible tube when theelongate flexible tube is straight. The rigidizing device is configuredto have a rigid configuration when vacuum or pressure is applied throughthe inlet and a flexible configuration when vacuum or pressure is notapplied through the inlet. The braid angle is configured to change asthe rigidizing device bends when the rigidizing device is in theflexible configuration.

This and other embodiments can include one or more of the followingfeatures. The braid angle can be between 10 and 35 degrees. The braidangle can be between 15 and 25 degrees. The rigidizing device in therigid configuration can be at least two times stiffer than therigidizing device in the flexible configuration. The rigidizing devicein the rigid configuration can be at least 5 times stiffer than therigidizing device in the flexible configuration. The rigidizing canfurther include a slip layer adjacent to the braid layer and having alower coefficient of friction than the braid layer. The elongateflexible tube can include a reinforcement element extending therein. Thereinforcement element can include a coil or plurality of hoop elements.The plurality of strands can be braided together at 4-60 picks per inch.The strands can include polyethylene terephthalate or stainless steel.The braid layer can provide a coverage of 30-70% relative to theelongate flexible tube. The plurality of strands can include 96 strandsor more. The inlet can be configured to attach to a source of pressure,and the rigidizing device can further include a bladder layer therein.The bladder layer can be configured to be pushed against the braid layerwhen pressure is supplied through the inlet. The outer layer can furtherinclude a plurality of reinforcement elements therein. The inlet can beconfigured to attach to a source of vacuum, and the outer layer can be athin flexible sheath. The rigidizing device can further include a radialgap between the braid layer and the outer layer. The gap can have athickness of 0.00002″-0.04″. The rigidizing device can further include asteerable distal end. The rigidizing device can further include a sealedchannel between the elongate flexible tube and the outer layer. Thesealed channel can include a working channel, a cable guide, or aninflation lumen.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a braid layer having a plurality of strands braided together at abraid angle of 5-40 degrees when the rigidizing device is straight, andan outer layer, and where the braid angle changes as the flexible tubebends in the flexible configuration; and (2) when the rigidizing devicehas reached a desired location in the body lumen, activating vacuum orpressure between the flexible tube and the outer layer to transition therigidizing device into a rigid configuration that is stiffer than theflexible configuration.

This and other embodiments can include one or more of the followingfeatures. The method can further include releasing vacuum or pressureafter activating the vacuum or pressure to transition the rigidizingdevice back to the flexible configuration. The braid angle can bebetween 10 and 35 degrees. The braid angle can be between 15 and 25degrees. The method can further include passing a scope through therigidizing device while the rigidizing device is in the rigidconfiguration. The method can further include steering a steerabledistal end of the rigidizing device through the body lumen. The bodylumen can be in the gastrointestinal tract. The body lumen can be in theheart. The body lumen can be in the kidneys. The body lumen can be inthe lungs. The body lumen can be in the brain.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a braid layer positioned over the elongate flexible tube,an outer layer over the flexible tube and the braid layer, and an inletbetween the elongate flexible tube and the outer layer and configured toattach to a source of vacuum or pressure. The rigidizing device isconfigured to have a rigid configuration when vacuum or pressure isapplied through the inlet and a flexible configuration when vacuum orpressure is not applied through the inlet. A ratio of stiffness of therigidizing device in the rigid configuration to stiffness of therigidizing device in the flexible configuration is greater than 5.

This and other embodiments can include one or more of the followingfeatures. The ratio can be greater than 6. The ratio can be greater than10. The braid layer can have a plurality of strands braided together ata braid angle of 5-40 degrees relative to a longitudinal axis of theelongate flexible tube when the elongate flexible tube is straight. Thebraid angle can be between 10 and 35 degrees. The rigidizing device canfurther include a slip layer adjacent to the braid layer and having alower coefficient of friction than the braid layer. The elongateflexible tube can include a reinforcement element extending therein. Thereinforcement element can include a coil or plurality of hoop elements.The braid layer can include a plurality of strands braided together at4-60 picks per inch. The braid layer can include a plurality of strandsbraided together, and the strands can include polyethylene terephthalateor stainless steel. The braid layer can provide a coverage of 30-70%relative to the elongate flexible tube. The braid layer can include 96strands or more strands braided together. The inlet can be configured toattach to a source of pressure. The rigidizing device can furtherinclude a bladder layer therein, and the bladder layer can be configuredto be pushed against the braid layer when pressure is supplied throughthe inlet. The outer layer can further include a plurality ofreinforcement elements therein. The inlet can be configured to attach toa source of vacuum. The outer layer can be a thin flexible sheath. Therigidizing device can further include a radial gap between the braidlayer and the outer layer. The gap can have a thickness of0.00002″-0.04″. The rigidizing device can further include a steerabledistal end. The rigidizing device can further include a sealed channelbetween the elongate flexible tube and the outer layer. The sealedchannel can include a working channel, a cable guide, or an inflationlumen.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a braid layer, and an outer layer; and (2) when the rigidizingdevice has reached a desired location in the body lumen, activatingvacuum or pressure between the flexible tube and the outer layer totransition the rigidizing device into a rigid configuration that isstiffer than the flexible configuration. A ratio of stiffness in therigid configuration to stiffness in the flexible configuration isgreater than 5.

This and other embodiments can include one or more of the followingfeatures. The method can further include releasing vacuum or pressureafter activating the vacuum or pressure to transition the rigidizingdevice back to the flexible configuration. The ratio can be greater than6. The ratio can be greater than 10. The method can further includepassing a scope through the rigidizing device while the rigidizingdevice is in the rigid configuration. The method can further includesteering a steerable distal end of the rigidizing device through thebody lumen. The body lumen can be in the gastrointestinal tract. Thebody lumen can be in the heart. The body lumen can be in the kidneys.The body lumen can be in the lungs. The body lumen can be in the brain.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a braid layer positioned radially outwards the elongateflexible tube, a slip layer adjacent to the braid layer, an outer layer,and a vacuum or pressure inlet between the elongate flexible tube andthe outer layer. The outer layer is over the flexible tube, the braidlayer, and the slip layer. The inlet is configured to attach to a sourceof vacuum or pressure. The rigidizing device is configured to have arigid configuration when vacuum or pressure is applied through the inletand a flexible configuration when vacuum or pressure is not appliedthrough the inlet. The slip layer is configured to reduce frictionbetween the braid layer and the elongate flexible tube or the outerlayer when the rigidizing device is in the flexible configuration.

This and other embodiments can include one or more of the followingfeatures. The slip layer can have a lower coefficient of friction thanthe braid layer. The slip layer can include a powder. The rigidizingdevice in the rigid configuration can be at least two times stiffer thanthe rigidizing device in the flexible configuration. The rigidizingdevice in the rigid configuration can be at least 5 times stiffer thanthe rigidizing device in the flexible configuration. The braid layer canhave a plurality of strands braided together at a braid angle of 5-40degrees relative to a longitudinal axis of the elongate flexible tubewhen the elongate flexible tube is straight. The braid angle can bebetween 10 and 35 degrees. The elongate flexible tube can include areinforcement element extending therein. The reinforcement element caninclude a coil or plurality of hoop elements. The braid layer caninclude a plurality of strands braided together at 4-60 picks per inch.The braid layer can include a plurality of strands braided together, andthe strands can include polyethylene terephthalate or stainless steel.The braid layer can provide a coverage of 30-70% relative to theelongate flexible tube. The braid layer can include 96 strands or morestrands braided together. The inlet can be configured to attach to asource of pressure. The rigidizing device can further include a bladderlayer therein. The bladder layer can be configured to be pushed againstthe braid layer when pressure is supplied through the inlet. The outerlayer can further include a plurality of reinforcement elements therein.The inlet can be configured to attach to a source of vacuum. The outerlayer can be a thin flexible sheath. The rigidizing device can furtherinclude a radial gap between the braid layer and the outer layer. Thegap can have a thickness of 0.00002″-0.04″. The rigidizing device canfurther include a steerable distal end. The rigidizing device canfurther include a sealed channel between the elongate flexible tube andthe outer layer. The sealed channel can include a working channel, acable guide, or an inflation lumen.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a braid layer, a slip layer adjacent to the braid layer, and anouter layer, and where the slip layer reduces friction between the braidlayer and the elongate flexible tube or the outer layer while therigidizing device is in the flexible configuration; and (2) when therigidizing device has reached a desired location in the body lumen,activating vacuum or pressure between the flexible tube and the sheathto transition the rigidizing device into a rigid configuration that isstiffer than the flexible configuration.

This and other embodiments can include one or more of the followingfeatures. The method can further include releasing vacuum or pressureafter activating the vacuum or pressure to transition the rigidizingdevice back to the flexible configuration. The slip layer can have alower coefficient of friction than the braid layer. The slip layer caninclude a powder. The method can further include passing a scope throughthe rigidizing device while the rigidizing device is in the rigidconfiguration. The method can further include steering a steerabledistal end of the rigidizing device through the body lumen. The bodylumen can be in the gastrointestinal tract. The body lumen can be in theheart. The body lumen can be in the kidneys. The body lumen can be inthe lungs. The body lumen can be in the brain.

In general, in one embodiment, a rigidizing device includes an innerelongate flexible tube including a reinforcement element and a matrix, abraid layer positioned radially outwards the elongate flexible tube, anouter layer over the braid layer, and a vacuum or pressure inlet betweenthe elongate flexible tube and the outer layer and configured to attachto a source of vacuum or pressure. The reinforcement element has a widthto thickness aspect ratio of over 5:1. The rigidizing device isconfigured to have a rigid configuration when vacuum or pressure isapplied through the vacuum inlet and a flexible configuration whenvacuum or pressure is not applied through the vacuum inlet.

This and other embodiments can include one or more of the followingfeatures. The reinforcement element can be a coil. The reinforcementelement can include a plurality of closed rings. The closed rings caninclude a plurality of pockets and notches. The reinforcement elementcan include an undulating wire. The reinforcement element can be a fiberor a metal wire. The aspect ratio can be over 10:1 The aspect ratio canbe over 11:1. There can be a plurality of reinforcement elements in theelongate flexible tube. A spacing between each of the reinforcementelements can be 0.0006″ inches or less. The elongate flexible tube canfurther include a matrix within which the reinforcement element isembedded. The matrix can include TPU or TPE.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube having a reinforcement element and a matrix, a braid layer, and anouter layer, and where the reinforcement element has a width tothickness aspect ratio of over 10:1; and (2) when the rigidizing devicehas reached a desired location in the body lumen, activating vacuum orpressure between the flexible tube and the outer layer to transition therigidizing device into a rigid configuration that is stiffer than theflexible configuration.

This and other embodiments can include or more of the followingfeatures. The elongate flexible tube can resist compression when vacuumor pressure is applied.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a braid layer positioned over the elongate flexible tube,an outer layer over the flexible tube and the braid layer, and an inletbetween the elongate flexible tube and the outer layer and configured toattach to a source of vacuum or pressure. The braid layer has aplurality of strands braided together. The rigidizing device isconfigured to have a rigid configuration when vacuum or pressure isapplied through the inlet and a flexible configuration when vacuum orpressure is not applied through the inlet. Ends of the strands areembedded in or surrounded by an annular ring that allows relativemovement of the ends when the rigidizing device is in the flexibleconfiguration.

This and other embodiments can include one or more of the followingfeatures. The annular ring can include a coating of material. Theannular ring can include silicone or urethane. The annular ring can beapproximately 0.005-0.250 inches thick.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a braid layer having a plurality of strands braided together, andan outer layer; and (2) when the rigidizing device has reached a desiredlocation in the body lumen, activating vacuum or pressure between theflexible tube and the sheath to transition the rigidizing device into arigid configuration that is stiffer than the flexible configuration.Ends of the strands are embedded in or surrounded by an annular ringsuch that the ends move relative to one another while the rigidizingdevice is in the flexible configuration. The ends are substantiallyfixed relative to one another while the rigidizing device is in therigid configuration.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a braid layer positioned over the elongate flexible tube,an outer layer sealed over the flexible tube and the braid layer, and aninlet between the elongate flexible tube and the outer layer andconfigured to attach to a source of vacuum. The braid layer has aplurality of strands braided together and a plurality of hoop fiberswoven into the braid. The rigidizing device is configured to have arigid configuration when vacuum is applied through the inlet and aflexible configuration when vacuum is not applied through the inlet.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a braid layer and an outer layer; and (2) when the rigidizingdevice has reached a desired location in the body lumen, activatingvacuum between the flexible tube and the outer layer to transition therigidizing device into a rigid configuration that is stiffer than theflexible configuration. The braid layer has a plurality of strandsbraided together and a plurality of hoop fibers woven into the braid.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a bladder layer positioned over the elongate flexibletube, a braid layer positioned over the bladder layer, an outer layerpositioned over the flexible tube and the braid layer, a pressure inletbetween the bladder layer and the elongate flexible tube, and a ventoutlet between the bladder layer and the outer layer. The pressure inletconfigured to attach to a source of pressure. The braid layer includes aplurality of strands braided together. The rigidizing device isconfigured to achieve a rigid configuration when pressure is suppliedthrough the pressure inlet and a flexible configuration when pressure isnot supplied through the pressure inlet. Fluid or gas surrounding thestrands moves out of the vent outlet as the rigidizing devicetransitions from the flexible configuration to the rigid configuration.

This and other embodiments can include one or more of the followingfeatures. The rigidizing device can further include a handle attached tothe elongate flexible tube. The handle can include a vent port incommunication with the vent outlet.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a bladder layer, a braid layer having a plurality of strandsbraided together, and an outer layer; and (2) when the rigidizing devicehas reached a desired location in the body lumen, providing pressurethrough an inlet between the elongate flexible tube and the bladderlayer and venting gas or fluid surrounding the strands out of a ventoutlet to transition the rigidizing device into a rigid configurationthat is stiffer than the flexible configuration.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a braid layer positioned over the elongate flexible tube,an outer layer over the flexible tube and the braid layer, a channelextending between the outer layer and the elongate flexible tube, and aninlet. The inlet is between the elongate flexible tube and the outerlayer and configured to attach to a source of vacuum or pressure. Thechannel includes a working channel, a steering cable channel, or aninflation lumen. The rigidizing device is configured to have a rigidconfiguration when vacuum or pressure is applied through the inlet and aflexible configuration when vacuum or pressure is not applied throughthe inlet.

In general, in one embodiment, a method of advancing a medical toolthrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a braid layer, and an outer layer; (2) when the rigidizing devicehas reached a desired location in the body lumen, activating vacuum orpressure between the flexible tube and the outer layer to transition therigidizing device into a rigid configuration that is stiffer than theflexible configuration; and (3) passing a medical tool through a sealedworking channel that is positioned between the elongate flexible tubeand the outer layer.

In general, in one embodiment, a method of advancing a medical toolthrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device comprises an elongateflexible tube, a braid layer, and an outer layer; (2) when therigidizing device has reached a desired location in the body lumen,activating vacuum or pressure between the flexible tube and the outerlayer to transition the rigidizing device into a rigid configurationthat is stiffer than the flexible configuration; and (3) activating atleast one cable that is positioned between the elongate flexible tubeand the outer layer to orient a distal end of the rigidizing device.

In general, in one embodiment, a method of advancing a medical toolthrough a body lumen includes: (1) inserting a rigidizing device intothe body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a braid layer, and an outer layer; (2) when the rigidizing devicehas reached a desired location in the body lumen, activating vacuum orpressure between the flexible tube and the outer layer to transition therigidizing device into a rigid configuration that is stiffer than theflexible configuration; and (3) inflating a balloon on the rigidizingdevice by passing an inflation medium through a sealed inflation lumenthat is positioned between the elongate flexible tube and the outerlayer.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube having a central lumen, a braid layer positioned over theelongate flexible tube, an outer layer over the flexible tube and thebraid layer, a plurality of sealed working channels extending within thecentral lumen, and an inlet between the elongate flexible tube and theouter layer and configured to attach to a source of vacuum or pressure.The rigidizing device is configured to have a rigid configuration whenvacuum or pressure is applied through the inlet and a flexibleconfiguration when vacuum or pressure is not applied through the inlet.

In general, in one embodiment, a method of advancing a plurality ofmedical tools through a body lumen includes: (1) inserting a rigidizingdevice into the body lumen while the rigidizing device is in a flexibleconfiguration, where the rigidizing device includes an elongate flexibletube, a braid layer, and an outer layer; (2) and when the rigidizingdevice has reached a desired location in the body lumen, activatingvacuum or pressure between the flexible tube and the outer layer totransition the rigidizing device into a rigid configuration that isstiffer than the flexible configuration; (3) passing a first medicaltool through a first sealed working channel of the rigidizing device,and (4) passing a second medical tool through a second sealed workingchannel of the rigidizing device.

In general, in one embodiment, an overtube includes an elongate tube anda distal tip attached to the elongate tube. The distal tip has anannular distal face with one or more vacuum holes extendingtherethrough. The one or more vacuum holes are configured to draw tissuetowards the annular distal face upon application of vacuum therethrough.

This and other embodiments can include one or more of the followingfeatures. The elongate tube can be a rigidizing device, and therigidizing device can be configured to have a rigid configuration whenvacuum or pressure is applied to a wall thereof and a flexibleconfiguration when vacuum or pressure is not applied to the wall. Theelongate tube can include a braid layer and an outer layer thereover.The annular distal face can be angled relative to a longitudinal axis ofthe elongate tube.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a braid layer positioned over the elongate flexible tube,an outer layer over the flexible tube and the braid layer, and a distaltip attached to the elongate flexible tube. The braid layer has aplurality of strands braided together at a first braid angle relative toa longitudinal axis of the elongate flexible tube when the elongateflexible tube is straight. The distal tip includes a second braid layerhaving a plurality of strands braided together at a second braid anglethat is different from the first braid angle. An inlet between theelongate flexible tube and the outer layer is configured to attach to asource of vacuum or pressure. The rigidizing device is configured tohave a rigid configuration when vacuum or pressure is applied throughthe inlet and a flexible configuration when vacuum or pressure is notapplied through the inlet.

This and other embodiments can include one or more of the followingfeatures. The second braid angle can be greater than the first braidangle. The first and second braid layers can be bonded to one another.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube including a plurality of reinforcement elements therein.The elongate flexible tube includes a proximal section and a distalsection. A braid layer is positioned over the proximal section and notthe distal section. The braid layer has a plurality of strands braidedtogether at a first braid angle relative to a longitudinal axis of theelongate flexible tube when the elongate flexible tube is straight. Anouter layer is positioned over the braid layer. A plurality of steerablelinkages extend over the distal section and not the proximal section. Aninlet is between the elongate flexible tube and the outer layer and isconfigured to attach to a source of vacuum or pressure. The rigidizingdevice is configured to have a rigid configuration when vacuum orpressure is applied through the inlet and a flexible configuration whenvacuum or pressure is not applied through the inlet.

This and other embodiment can include one or more of the followingfeatures. The rigidizing device can further include a plurality ofcables attached to the steerable linkages. The cables can extend betweenthe elongate flexible tube and the outer layer.

In general, in one embodiment, a rigidizing device includes a rigidizingassembly and plurality of linkages. The rigidizing assemble includes anelongate flexible tube, a braid layer positioned over the elongateflexible tube, an outer layer over the flexible tube and the braidlayer, and an inlet. The inlet is between the elongate flexible tube andthe outer layer and is configured to attach to a source of vacuum orpressure. The plurality of steering linkages are mounted over a distalportion of the rigidizing assembly. The rigidizing assembly isconfigured to have a rigid configuration when vacuum or pressure isapplied through the inlet and a flexible configuration when vacuum orpressure is not applied through the inlet.

This and other embodiments can include one or more of the followingfeatures. The rigidizing device can further include a plurality ofcables attached to the steerable linkages. The cables can extend betweenthe elongate flexible tube and the outer layer.

In general, in one embodiment, a rigidizing device includes an elongateflexible tube, a plurality of steerable linkages and an outlet. Theelongate flexible tube includes a proximal section and a distal section.The elongate flexible tube includes a plurality of reinforcementelements therein, a braid layer positioned over the proximal section thedistal section, an outer layer including a plurality of reinforcementelements. The plurality of steerable linkages extends over the distalsection and not the proximal section. The inlet is between the elongateflexible tube and the outer layer and configured to attach to a sourceof vacuum or pressure. The braid layer has a plurality of strandsbraided together at a first braid angle relative to a longitudinal axisof the elongate flexible tube when the elongate flexible tube isstraight. The outer layer is positioned over the proximal section andnot the distal section. The rigidizing device is configured to have arigid configuration when vacuum or pressure is applied through the inletand a flexible configuration when vacuum or pressure is not appliedthrough the inlet.

This and other embodiments can include one or more of the followingfeatures. The rigidizing device can further include a plurality ofcables attached to the steerable linkages. The cables can extend betweenthe elongate flexible tube and the outer layer.

In general, in one embodiment, a rigidizing device includes a rigidizingassembly and a plurality of linkages. The rigidizing assembly includesan elongate flexible tube, a braid layer positioned over the elongateflexible tube, an outer layer over the flexible tube and the braidlayer, and an inlet between the elongate flexible tube and the outerlayer and configured to attach to a source of vacuum or pressure. Aspine extends through a distal section of the rigidizing assembly. Thespine is configured to provide bending of the rigidizing assembly in aset direction. The plurality of steering linkages are distal to therigidizing assembly. The rigidizing assembly is configured to have arigid configuration when vacuum or pressure is applied through the inletand a flexible configuration when vacuum or pressure is not appliedthrough the inlet.

This and other embodiments can include one or more of the followingfeatures. The rigidizing device can further include a pullwireconfigured to bend the device at the spine when activated. Therigidizing device can further include a plurality of cables attached tothe steerable linkages. The cables can extend between the elongateflexible tube and the outer layer.

In general, in one embodiment, a rigidizing device includes a rigidizingassembly and a distal tip. The rigidizing assembly includes an elongateflexible tube, a braid layer positioned over the elongate flexible tube,an outer layer over the flexible tube and the braid layer, and an inletbetween the elongate flexible tube and the outer layer and configured toattach to a source of vacuum or pressure. The distal tip is attached tothe elongate flexible tube. The distal tip includes a plurality oflinkages connected together at pivot points. The rigidizing assembly andthe distal tip are configured to assume a rigid configuration whenvacuum or pressure is applied through the inlet and a flexibleconfiguration when vacuum or pressure is not applied through the inlet.

In general, in one embodiment, a handle for use with a rigidizing deviceincludes a handle body configured to attach to a rigidizing device, avacuum feed line attached to the handle body and configured to connectto a source of vacuum, a vacuum port in communication with a wall of therigidizing device, and an activation element on the handle body. Theactivation element is configured to move between a first position and asecond position. The activation element in the first position connectsthe vacuum feed line with the vacuum port to provide vacuum to the wallof the rigidizing device, and the activation element in the secondposition disconnects the vacuum feed line from the vacuum port to ventthe wall of the rigidizing device.

This and other embodiments can include one or more of the followingfeatures. The activation element can include a magnetic element thereon.The magnetic element can be configured to hold the activation element inthe first position or the second position. The vacuum feed line can becoiled within the handle.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) holding a handle of the rigidizingdevice; (2) inserting an elongate body of the rigidizing device into thebody lumen while the rigidizing device is in a flexible configuration;(3) when the rigidizing device has reached a desired location in thebody lumen, moving an activation element in a first direction to connecta vacuum feed line of the handle with a vacuum port to a wall of theelongate body such that vacuum flows into the wall of the elongate bodyto transition the elongate body to a rigid configuration; and (4) movingthe activation element in a second direction to disconnect the vacuumfeed line from the vacuum port such that the elongate body vents totransition the elongate body to the flexible configuration.

In general, in one embodiment, a handle for use with a rigidizing deviceincludes a handle body configured to attach to a rigidizing device, afluid chamber within the handle body, an outlet in fluid communicationwith the fluid chamber and with a wall of the rigidizing device, and anactivation element configured to move between a first position and asecond position. The activation element is configured to transfer fluidfrom the fluid chamber to the wall of the rigidizing device when movingfrom the first position to the second position and to transfer fluidback into the fluid chamber when moving from the second position to thefirst position.

This and other embodiments can include one or more of the followingfeatures. The handle can further include an overflow chamber within thehandle body and a pressure relief valve between the fluid chamber andthe overflow chamber. The pressure relief valve can be configured toopen to allow fluid to flow into the overflow chamber when pressure inthe fluid chamber reaches a predetermined maximum pressure. The handlecan further include a piston and rolling diaphragm within the handlebody. The piston can be configured to push on the rolling diaphragm asthe activation element is moved between the first position and thesecond position.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) holding a handle of the rigidizingdevice, (2) inserting an elongate body of the rigidizing device into thebody lumen while the rigidizing device is in a flexible configuration;(3) when the rigidizing device has reached a desired location in thebody lumen, moving an activation element in a first direction to movefluid from a fluid chamber of the handle into a wall of the rigidizingelement to transition the rigidizing device to a rigid configuration;and (4) moving the activation in a second direction to move fluid fromthe wall of the rigidizing element back into the handle to transitionthe rigidizing device to the flexible configuration.

In general, in one embodiment, a nested system includes a firstrigidizing device and a second rigidizing device positioned radiallywithin the first rigidizing device. The second rigidizing device isaxially slideable relative to the first rigidizing device. The first andsecond rigidizing devices are configured to be alternately rigidized byvacuum or pressure.

This and other embodiments can include one or more of the followingfeatures. The pressure can be greater than 1 atm. The first rigidizingdevice can be configured to be rigidized by vacuum and the secondrigidizing device can be configured to be rigidized by pressure ofgreater than 1 atm. Each of the first and second rigidizing devices caninclude a plurality of layers. The vacuum or pressure can be configuredto be supplied between the plurality of layers. At least one of theplurality of layers can be a braid layer.

In general, in one embodiment, a method of advancing through a bodylumen includes: (1) inserting a first rigidizing device into the bodylumen while the first rigidizing device is in a flexible configuration;(2) supplying vacuum or pressure to the first rigidizing device totransition the first rigidizing device into a rigid configuration thatis stiffer than the flexible configuration; (3) inserting a secondrigidizing device in a flexible configuration through the firstrigidizing device while the first rigidizing device is in the rigidconfiguration such that the second rigidizing device takes on a shape ofthe first rigidizing device in the rigid configuration; and (4)supplying vacuum or pressure to the second rigidizing device totransition the second rigidizing device from the flexible configurationto a rigid configuration.

This and other embodiments can include one or more of the followingfeatures. Each rigidizing device can include an elongate flexible tubeand a braid layer. Supplying vacuum or pressure can compress the braidlayer to transition the rigidizing device to the rigid configuration.

In general, in one embodiment, a method of advancing through a bodylumen includes: (1) moving a first rigidizing device in a flexibleconfiguration until the first rigidizing device reaches a desiredlocation; (2) after the first rigidizing device has reached the desiredlocation, transitioning the first rigidizing device into a rigidconfiguration by supplying vacuum or pressure to the first rigidizingdevice; (3) after the first rigidizing device is rigidized, moving asecond rigidizing device in a flexible configuration over the firstrigidizing device in the rigidized configuration; (4) transitioning thesecond rigidizing element into a rigid configuration by supplying vacuumor pressure to the second rigidizing device; (5) transitioning the firstrigidizing device into a flexible configuration by removing the vacuumor pressure; and (6) moving the first rigidizing device in the flexibleconfiguration through the second elongate rigidizing device until thefirst rigidizing device reaches a desired location.

This and other embodiments can include one or more of the followingfeatures. The method can further include periodically moving both thefirst and second rigidizing devices into a flexible configuration toallow a curvature of the first and second rigidizing devices to increaseto match surrounding anatomy.

In general, in one embodiment, a rigidizing rod includes an innerbladder layer, a braid layer positioned over the inner bladder layer, anouter sheath sealed over the inner bladder layer and the braid layer,and an inlet between the outer sheath and the inner bladder layerconfigured to attach to a source of vacuum. The rigidizing rod isconfigured to have a rigid configuration when vacuum is applied throughthe inlet and a flexible configuration when vacuum or pressure is notsupplied through the inlet. The rigidizing rod does not have athrough-lumen extending therethrough.

In general, in one embodiment, a method of advancing a rigidizing devicethrough a body lumen includes: (1) advancing the rigidizing devicethrough the body lumen; (2) inserting a rod having an elongate flexibletube, a braid layer, and a bladder into a lumen of the rigidizing devicewhile the rod is in a flexible configuration; (3) when the rod hasreached a desired location in the lumen of the rigidizing device,supplying pressure of greater than 1 atm to a central sealed lumen ofthe rod to force the braid layer against the elongate flexible tube totransition the rigidizing device into a rigid configuration that isstiffer than the flexible configuration; and (4) further advancing therigidizing device over the rod while the rod is in the rigidconfiguration.

In general, in one embodiment, a method of performing cholangioscopyincludes: (1) inserting an overtube into colon while the overtube is ina flexible configuration, where the overtube includes an elongateflexible tube, a braid layer having a plurality of strands braidedtogether, and an outer layer; (2) steering a distal end of the overtubetowards a papilla; (3) activating vacuum or pressure between theflexible tube and the outer layer to transition the overtube into arigid configuration that is stiffer than the flexible configuration; (4)while the overtube is in the rigid configuration, advancing a guidewirethrough the overtube and into a bile duct or pancreatic duct; and (5)advancing a scope over the guidewire to the bile duct or pancreaticduct.

In general, in one embodiment, a method of accessing the cardiac anatomyincludes: (1) inserting a sheath into the cardiac anatomy while thesheath is in the flexible configuration, where the sheath includes anelongate flexible tube, a braid layer having a plurality of strandsbraided together, and an outer layer; (2) steering a distal end of thesheath towards a desired final location; (3) activating vacuum orpressure between the flexible tube and the outer layer to transition theovertube into a rigid configuration that is stiffer than the flexibleconfiguration; and (4) passing a cardiac device through the rigidsheath.

This and other embodiments can include one or more of the followingfeatures. The desired final location can be the aortic valve. Thecardiac device can be a transcatheter aortic valve replacement. Thedesired final location can be the mitral valve. The cardiac device canbe a mitral valve replacement or a mitral valve repair element.

Any of the devices described here can include one or more of thefollowing. The rigidizing device can further include a slip layeradjacent to the braid layer. The slip layer can have a lower coefficientof friction than the braid layer. The rigidizing device in the rigidconfiguration can be at least two times stiffer than the rigidizingdevice in the flexible configuration. The rigidizing device in the rigidconfiguration can be at least 5 times stiffer than the rigidizing devicein the flexible configuration. The braid layer can have a plurality ofstrands braided together at a braid angle of 5-40 degrees relative to alongitudinal axis of the elongate flexible tube when the elongateflexible tube is straight. The braid angle can be between 10 and 35degrees. The elongate flexible tube can include a reinforcement elementextending therein. The reinforcement element can include a coil orplurality of hoop elements. The braid layer can include a plurality ofstrands braided together at 4-60 picks per inch. The braid layer caninclude a plurality of strands braided together. The strands can includepolyethylene terephthalate or stainless steel. The braid layer canprovide a coverage of 30-70% relative to the elongate flexible tube. Thebraid layer can include 96 strands or more strands braided together. Theinlet can be configured to attach to a source of pressure. Therigidizing device can further include a bladder layer therein. Thebladder layer can be configured to be pushed against the braid layerwhen pressure is supplied through the inlet. The outer layer can furtherinclude a plurality of reinforcement elements therein. The inlet can beconfigured to attach to a source of vacuum. The outer layer can be athin flexible sheath. The rigidizing device can further include a radialgap between the braid layer and the outer layer. The gap can have athickness of 0.00002″-0.04″. The rigidizing device can further include asteerable distal end. The rigidizing device can further include a sealedchannel between the elongate flexible tube and the outer layer. Thesealed channel can include a working channel, a cable guide, or aninflation lumen.

Any of the methods described here can include one or more of thefollowing. The method can further include releasing vacuum or pressureafter activating the vacuum or pressure to transition the rigidizingdevice back to the flexible configuration. The method can be performedin the gastrointestinal tract. The method can be performed in the heart.The method can be performed in the kidneys. The method can be performedin the lungs. The method can be performed in the brain.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe claims that follow. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1 shows a rigidizing device.

FIGS. 2A-2B show portions of a braid layer of a rigidizing device.

FIG. 3 is a graph of bend force vs braid angle when a rigidizing deviceis placed under vacuum.

FIGS. 4A-4D show exemplary braid formations.

FIGS. 5A-5B show exemplary braid formations.

FIGS. 6A-6D various designs for the termination of braid layers of arigidizing device.

FIG. 7 shows an inner layer of a rigidizing device.

FIGS. 8A-8F show different coil designs for a layer of a rigidizingdevice.

FIGS. 9A-9B show undulating reinforcement elements for a layer of arigidizing device.

FIGS. 10A-10E show notch and pocket reinforcement elements for a layerof a rigidizing device.

FIGS. 11A-11B show a cut tubing reinforcement element for a layer of arigidizing device.

FIGS. 12A-12B show exemplary rigidized shapes of a rigidizing device.

FIGS. 13A-13D show an exemplary vacuum rigidizing device.

FIGS. 14A-14B show an exemplary pressure rigidizing device.

FIG. 15 is a graph of bending strength vs pressure for a rigidizingdevice.

FIG. 16A-16O show various examples of pressure rigidizing devices.

FIGS. 17A-17D show a rigidizing device with an incorporated workingchannel.

FIGS. 18A-18B show a rigidizing device with a spiraled working channel.

FIGS. 19A-19B show a rigidizing device with a plurality of spiraledworking channels.

FIGS. 20A-20B show a rigidizing device with a plurality of workingchannels extending down the central lumen.

FIG. 21 shows a rigidizing device with a working channel extending outthe side thereof.

FIG. 22 shows a tool that can be used with a working channel of adevice, such as a rigidizing device.

FIG. 23 shows a rigidizing device with a distal end section.

FIG. 24 shows a rigidizing device with a distal end section having aseparate braid pattern from the proximal section of the device.

FIG. 25 shows a rigidizing device with a distal end section having aplurality of passive linkages.

FIG. 26 shows a rigidizing device with a distal end section having aplurality of actively controlled linkages.

FIGS. 27A-27E shows a plurality of actively controlled linkages.

FIG. 28 shows one embodiment of a rigidizing device including cablesextending within the layered wall.

FIG. 29 shows one embodiment of a rigidizing device including cablesextending within the layered wall.

FIG. 30 shows one embodiment of a rigidizing device including cablesextending within the layered wall.

FIG. 31 shows one embodiment of a rigidizing device including cablesextending within the layered wall.

FIG. 32 shows one embodiment of a rigidizing device including cablesextending within the layered wall.

FIG. 33 shows one embodiment of a rigidizing device including cablesextending within the layered wall.

FIG. 34 shows one embodiment of a rigidizing device including cablesextending within the layered wall.

FIG. 35 shows a rigidizing device including cables extending down thecentral lumen.

FIG. 36 shows an embodiment of rigidizing device including a cablespiraled therearound.

FIG. 37 shows an embodiment of a rigidizing device with a cable spiraledtherearound.

FIGS. 38A-38B show an embodiment of a rigidizing device with a cablespiraled therearound.

FIGS. 39A-39B show a rigidizing device with a cable spiraled therein.

FIGS. 40A-40D show exemplary linkages for a distal end section.

FIGS. 41A-41B show a rigidizing device with a distal end section havinglinkages over a rigidizing section.

FIG. 42A shows a rigidizing device with a distal end section havinglinkages within a rigidizing section.

FIG. 42B shows a rigidizing device with a steering cable attached to awall near the distal end thereof.

FIGS. 43A-43C show a rigidizing device having an actively deflecteddistal end section.

FIGS. 44A-44C show a rigidizing device with separate rigidizing chambersalong the length thereof.

FIGS. 45A-45D show a rigidizing device with a balloon and inflationlumen.

FIGS. 46A-46B show an embodiment of a suction tip for a device such as arigidizing device.

FIGS. 47A-47B show an embodiment of a suction tip for a device such as arigidizing device.

FIGS. 48A-48B show an embodiment of a suction tip for a device such as arigidizing device.

FIGS. 49A-49D show an embodiment of a handle for use with a rigidizingdevice.

FIGS. 50A-50B show an embodiment of an activation element for a handleof a rigidizing device.

FIGS. 51A-51C show an embodiment of an activation element for a handleof a rigidizing device.

FIGS. 52A-52C show an embodiment of an activation element with acoupling for a handle of a rigidizing device.

FIGS. 53A-53D show an embodiment of a handle for use with a rigidizingdevice.

FIGS. 54A-54B show an embodiment of a handle for use with a rigidizingdevice.

FIGS. 55A-55C show an embodiment of an activation element for a handleof a rigidizing device.

FIGS. 56A-56G show an embodiment of a handle for use with a vacuumrigidizing device.

FIGS. 57A-57C show an embodiment of a handle for use with a pressurerigidizing device.

FIGS. 58A-58E show a pre-filled handle for use with a pressurerigidizing device.

FIG. 59 shows a rigidizing device with imaging elements mounted on aside thereof.

FIG. 60 shows a rigidizing introducer.

FIGS. 61A-61B show a rigidizing device with a side-access mechanism.

FIG. 62 shows a nested rigidizing system.

FIG. 63 shows a nested rigidizing system with a cover between the innerand outer rigidizing devices.

FIGS. 64A-64B show a nested rigidizing system where the outer rigidizingdevice includes steering and imaging.

FIGS. 65A-65H show exemplary use of a nested rigidizing system.

FIG. 66 shows a rigidizing rod.

FIG. 67 shows a rigidizing rod in use with a colonoscope.

FIGS. 68A-68B show an exemplary rigidizing device with a scope therein.

FIGS. 69A-69B show use of a rigidizing device in the gastrointestinaltract.

FIGS. 70A-70B show a method of use of a rigidizing device for ERCP.

FIGS. 71A-71B show a method of use of a rigidizing device for ERCP.

FIGS. 72A-72D show a method of use of a rigidizing device for ERCP.

FIGS. 73A-73B show a method of use of a rigidizing device in the heartto create access to the left atrium.

FIGS. 74A-74B show a method of use of a rigidizing device in the heartto perform treatment of a branching vessel.

FIGS. 75A-75C show a method of use of a rigidizing device in the heartfor mitral valve repair.

FIGS. 76A-76B show a method of use of a dual rigidizing device in theheart.

FIG. 77 shows a rigidizing device used as a trocar.

FIG. 78 shows a rigidizing device in use at the aortic bifurcation.

FIG. 79 shows a rigidizing device for mitral valve repair.

FIG. 80 shows a rigidizing device with a distal payload for mitral valverepair.

FIGS. 81A-81F show a method of using a rigidizing device to control aworking tool.

DETAILED DESCRIPTION

In general, described herein are rigidizing devices (e.g., overtubes)that are configured to aid in transporting a scope (e.g., endoscope) orother medical instrument through a curved or looped portion of the body(e.g., a vessel). The rigidizing devices can be long, thin, and hollowand can transition quickly from a flexible configuration (i.e., one thatis relaxed, limp, or floppy) to a rigid configuration (i.e., one that isstiff and/or holds the shape it is in when it is rigidized). A pluralityof layers (e.g., coiled or reinforced layers, slip layers, braidedlayers, bladder layers and/or sealing sheaths) can together form thewall of the rigidizing devices. The rigidizing devices can transitionfrom the flexible configuration to the rigid configuration, for example,by applying a vacuum or pressure to the wall of the rigidizing device orwithin the wall of the rigidizing device. With the vacuum or pressureremoved, the layers can easily shear or move relative to each other.With the vacuum or pressure applied, the layers can transition to acondition in which they exhibit substantially enhanced ability to resistshear, movement, bending, and buckling, thereby providing systemrigidization.

The rigidizing devices described herein can provide rigidization for avariety of medical applications, including catheters, sheaths, scopes(e.g., endoscopes), wires, or laparoscopic instruments. The rigidizingdevices can function as a separate add-on device or can be integratedinto the body of catheters, sheaths, scopes, wires, or laparoscopicinstruments. The devices described herein can also provide rigidizationfor non-medical structures.

An exemplary rigidizing device system is shown in FIG. 1. The systemincludes a rigidizing device 300 having a wall with a plurality oflayers including a braid layer, an outer layer (part of which is cutaway to show the braid thereunder), and an inner layer. The systemfurther includes a handle 342 having a vacuum or pressure inlet 344 tosupply vacuum or pressure to the rigidizing device 300. An actuationelement 346 can be used to turn the vacuum or pressure on and off tothereby transition the rigidizing device 300 between flexible and rigidconfigurations. The distal tip 339 of the rigidizing device 300 can besmooth, flexible, and atraumatic to facilitate distal movement of therigidizing device 300 through the body. Further, the tip 339 can taperfrom the distal end to the proximal end to further facilitate distalmovement of the rigidizing device 300 through the body.

A portion of an exemplary braid layer 209 for a rigidizing devicesimilar to device 300 is shown in FIGS. 2A-2B. The braid layer 209 canincluded braided strands 233. The braid layer 209 can, for example, be atubular braid.

The braid angle α of the strands 233 relative to the longitudinal axis235 of the rigidizing device when the rigidizing device (e.g., device300) is in a straight (unbent) configuration can be less than 45degrees, such as less than or equal to 40 degrees, less than or equal to35 degrees, or less than or equal to 25 degrees. Referring to FIG. 3,the bending strength of the rigidizing device decreases as the braidangle α (when the rigidizing device is straight or unbent) increases.That is, the bending strength under vacuum of the rigidizing device witha braid angle of 45 degrees (a typical minimum angle for a torque ortorsion braid. Still larger angles are typically used for catheter shaftreinforcement) under vacuum is 27% of the bending strength under vacuumof a rigidizing device with a braid angle of 25 degrees. Accordingly,having a lower braid angle (e.g., less than 45 degrees, such as 40degrees or less or 35 degrees or less) advantageously ensures that therigidizing device (e.g., device 300) remains stiff in bending (resistantto a change in configuration) under vacuum (and similarly underpressure). Additionally, the braid angle α when the rigidizing device isin a straight (unbent) configuration can be greater than 5 degrees, suchas greater than 8 degrees, such as greater than 10 degrees, such as 15degrees or greater. Having a braid angle α within this range ensuresthat the braid remains flexible enough to bend when in the flexibleconfiguration (i.e., when not rigidized under vacuum or pressure). Thus,the braid angle α of the strands 233 relative to the longitudinal axis235 of the rigidizing device when the rigidizing device is in a straightconfiguration can be 5 to 40 degrees, such as 10 to 35 degrees, such as15 to 25 degrees, such as approximately 5, 10, 15, 20, 25, 30, 35, or 40degrees. The braid angle α of the strands 233 relative to thelongitudinal axis 235 of the rigidizing device when the rigidizingdevice is in a straight (unbent) configuration of 5-40 degrees ensuresthat the rigidizing device is flexible enough to bend in the flexibleconfiguration (e.g., when not under vacuum/pressure) yet stiff when inthe rigid configuration (e.g., when placed under vacuum or pressure).Additionally, it should be understood that the strands 233 areconfigured to slide over one another, and therefore that the braid angleα will change the rigidizing device flexes and bends. Having an angle αthat is between 5 and 40 degrees also advantageously ensures that thestrands 233 can move freely relative to one another without causing thefibers to collide with one another and prevent further angular change.

Further, the braid for braid layer 209 can be between 4-60 picks perinch, such as 8, 10, 12, 14, 16, 18, 20, or 25 picks/inch. In oneembodiment, the tube formed by the layer 209 has a diameter of 0.578″,and the braid is 12-14 picks per inch.

In some embodiments, the braid layer 209 (or any braid layer describedherein) can be configured such that the rigidizing devices describedherein have a high stiffness ratio (i.e., the ratio of the stiffness inthe rigid configuration, such as when vacuum or pressure is applied, tostiffness in the flexible configuration, such as when vacuum or pressureis not applied). For example, the stiffness ratio can be greater than 5,such as greater than 6, greater than 9, greater than 9, or greater than10. Referring to Table 1 below, six vacuum rigidizing devices (samplesA-F) were built and tested over a length of 4″ and a deflection of ½″for cantilevered bending stiffnesses at atmospheric pressure (flexibleconfiguration) and under vacuum (rigid configuration). As shown,lowering the braid angles raises the stiffness of the rigidized devices.Samples E and F show, in particular, the stiffness difference between abraid at a typical torque angle (sample E, 47.7 degrees and rigidstiffness of 0.529 lbf) and a braid with a lower angle (sample F, 27.2degrees, and a rigid stiffness of 1.455 lbf). As is also shown in Table1, rigidizing devices with lower angles (e.g., angles under 45 degreesor 35 degrees, such as samples A-D and F) can have a much higherstiffness ratio (e.g., ratio of greater than 5, greater than 6, greaterthan 9, or greater than 10) than rigidizing devices with higher angles(e.g., angles of 45 degrees or above, such as sample F), which can havea stiffness ratio of under 5. It can also be observed from Table 1 thatboth samples A and B have a stiffness ratio above 5. Sample B, at a 14.9degree braid angle, has a lower stiffness ratio but a higher absolutestiffness than sample because the strands of sample B are oriented closeto the longitudinal axis (and therefore sample B has a higher stiffnessin the flexible configuration).

TABLE 1 Vacuum Rigidizing Devices Inside Braid Flexible Rigid Change indiameter angle Picks stiffness stiffness Stiffness Stiffness Sample(Inches) (degrees) Strand per Inch (lbf) (lbf) ratio (lbf) A 0.37 20.40.010″ 14.3 0.046 0.441 9.6 0.395 PET B 0.37 14.9 0.010″ 12.8 0.0970.653 6.7 0.556 PET C 0.576 32.8 0.010″ 16.2 0.099 0.661 6.7 0.562 PET D0.576 20 0.010″ 11.5 0.115 1.102 9.6 0.987 PET E 0.77 47.7 0.010″ 19.80.115 0.529 4.6 0.414 PET F 0.77 27.2 0.010″ 12.2 0.137 1.455 10.6 1.318PET

Referring to Table 2 below, three pressure rigidizing devices (samplesG-I) were built and tested over a length of 4″ and a deflection of ½″for cantilevered bending stiffnesses at atmospheric pressure atmosphericpressure (flexible configuration) and under 4 atm pressure (rigidconfiguration). The samples all included a coverage of 35-45% and abraid with 96 strands and one filament per strand. As shown, loweringthe braid angles raises the stiffness of the rigidizing devices. As isalso shown in Table 2, rigidizing devices with lower angles can have ahigher stiffness ratio than rigidizing devices with higher angles. Insome embodiments, the pressure rigidizing devices described herein havea stiffness ratio of greater than 10, such as greater than 15, such asgreater than 20.

TABLE 2 Pressure Rigidizing Devices Inside Braid Flexible Rigid Changein diameter angle Picks stiffness stiffness Stiffness Stiffness Sample(inches) (degrees) Strand per inch (lbf) (lbf) ratio (lbf) G 0.35 300.005″ 24.1 0.044 0.448 10.2 0.404 stainless steel H 0.35 22.7 0.005″17.5 0.037 0.611 16.5 0.574 stainless steel I 0.35 15.6 0.005″ 11.70.051 1.091 21.4 1.04 stainless steel

Further, in some embodiments, the braid of braid layer 209 can have acoverage of 30%-70%, such as 40%-60%, e.g., 30%, 40%, 50%, 60%, or 70%,where the coverage area is the percentage of an underlying surface thatis covered or obstructed by the braid.

In some embodiments, the braid layer 209 can be formed by running eachindividual strand around an inner tube or the rigidizing device and/or aseparate mandrel in a helix such that the strands 233 are interlacedwith one another. In one embodiment, the braid layer 209 can be heatformed over a 0.50″-0.60″, e.g., 0.56″ mandrel. Further, in someembodiments, the braid layer during manufacturing can be mounted over atube or mandrel to a diameter that is smaller than the core diameter(i.e., smaller than the diameter at which the braid was originallymanufactured). Compressing the braid radially in this way can decreasethe braid angle in the range that provides a high rigidization multiple(while also decreasing the PPI, increasing the total length of thetubular braid layer, and increasing the braid coverage percentage).

The strands 233 can be rectangular/flat (e.g., with a long edge of0.001″-0.060″, such as 0.005″, 0.007″, 0.010″, or 0.012″, and a shortedge of 0.0003″-0.030″, such as 0.001″, 0.002″, or 0.003″), round (e.g.,with a diameter of 0.001″-0.020″, such as 0.005″, 0.01″, or 0.012″), oroval. In some embodiments, some of the strands 233 can be flat and someof the strands 233 can be round.

In some embodiments, the strands 233 can be made of metal filaments(e.g., stainless steel, aluminum, nitinol, tungsten, or titanium),plastic (nylon, polyethylene terephthalate, PEEK, polyetherimide), orhigh strength fiber (e.g., aramids, ultra-high molecular weight UHMWpolyethylene, or liquid crystal polymers such as Vectran). In someembodiments, the strands 233 can be made of a multi-layer composite,such as a metal core with a thin elastomeric coating. In one specificexample, the strands 233 can include round nylon having a diameter of0.010″ (or metal filaments having a diameter of 0.003″) intertwined withflat aluminized PET with cross-sectional dimensions of 0.002″ by 0.002″.In some embodiments, the material for the strands 233 of the braid canbe a material with a known high coefficient of friction. For example,the strands 233 can be a monolithic structure or have a coating suchthat the strands include aluminum on aluminum, copper on copper, silveron silver, or gold on gold. As another example, the strands 233 can becoated with an elastomeric material (e.g., lower durometer elastomerscan be coated on top of a higher modulus substrate). As another example,the strands 233 can be made of styrene co-polymer, polycarbonate, oracrylic.

There can be between 12-800 strands 233, such as 24, 48, 96, 120, 144 ormore strands 233 extending within braid layer 209. In some embodiments,there are 96 strands or more, 120 strands or more, 200 strands or more,or 240 strands or more. A higher number of strands may advantageouslyhelp rigidize the braid due to the increased interaction betweenstrands.

Referring to FIGS. 4A-4D, the braid of any of the rigidizing devicesdescribed herein can be in a variety of different braid patterns. Forexample, referring to FIG. 4A, the braid of layer 1709 can be a diamondfull load pattern in which two neighboring strands 1733 a,b extend overtwo strands and then under two strands. Referring to FIG. 4B, the braidof layer 1709 can be a full load pattern, in which each strand 1733 aextends over two strands and under two strands in a manner that isopposite to the neighboring strand 1733 b. Referring to FIG. 4C, thebraid of layer 1709 can be a diamond half load pattern in which eachstrand 1733 a extends over one strand and under one strand opposite tothe neighboring strand 1733 b. Referring to FIG. 4D, the braid of layer1709 can include one or more longitudinal strands 1733 c running throughthe crossed strands 1733 a, 1733 b.

Referring to FIGS. 5A-5B, each strand 1833 can include a single filament1818 (FIG. 5A) or multiple filaments 1818 a-c (three filaments 1818 a-care shown in each strand 1833 in FIG. 5B). The filaments 1818 can bechosen (i.e., diameter, spacing, and modulus can be specificallytailored) to reduce crimp (the waviness or bending of the filaments).Reduced crimp can help the system provide enhanced compression bucklingresistance, which can translate to enhanced system stiffness.

Exemplary specific braid layer embodiments J-N are shown in Table 3.

TABLE 3 Exemplary braids Inside Braid Number of diameter angle PicksNumber of filaments Pattern of Braid Rigidizing Sample (inches)(degrees) Strand per inch strands per strand crossing coverage medium J0.576 20 PET, 12 120 1 Full 56.7%  Vacuum round, load 0.010″ K 0.21 15.1Stainless 18.7 96 1 Full 59% Pressure steel, load round, 0.005″ L 0.3525.7 Stainless 20.45 96 1 Full 42% Pressure steel, load round, 0.005″ M0.21 15.1 Stainless 18.7 96 1 Full 50% Pressure steel, load round,0.004″ N 0.33 14 Stainless 11.7 96 1 Full 42% Pressure steel, loadround, 0.005″

In use, vacuum or pressure can be supplied between the walls of therigidizing devices described herein, causing the braided layer andneighboring layer(s) to constrict and/or separate to transition betweenflexible and rigid configurations. The rigidizing devices describedherein can thus advantageously transition from very flexible to verystiff upon activation by the user. When a vacuum or pressure is applied,the braids or strands can radially constrict or expand to becomemechanically fixed or locked in place relative to one another. As aresult, the rigidizing device can go from a flexible configuration to arigid configuration when vacuum or pressure is applied (thereby fixingthe rigidizing device in the shape that the rigidizing device was injust prior to application of the vacuum or pressure).

Referring to FIGS. 6A-6D, in some embodiments, one or both ends of thebraid layer 5609 of a rigidizing device 5600 as described herein can bebonded to another layer of the device 5600 to prevent the strands 5633of the braid from coming unbraided. Further, the ends of the strands5633 can be bonded in such a way so as to allow relative movement of thestrands 5633 during flexing of the rigidizing device 5600 when it is inthe flexible configuration (i.e., so as to prevent rigidity or bucklingof the device 5600, which in turn can lead to drag at the tip 5629, thatmight otherwise occur if the strands 5633 were constrained).

For example, as shown in FIG. 6A, the tip 5629 of the braid layer 5609can include a coating 5634 thereover of low durometer material, such assilicone or urethane, that is stretchable and/or flexible. As a result,the ends of the strands 5633 can be encapsulated by the coating 5634(and therefore prevented from unbraiding) while still moving withcoating 5634 as it stretches and/or flexes. The coating 5634 can bethin, such as between 0.005-0.250 thick (e.g., approximately 1/32″thick).

As another example, as shown in FIG. 6B, the tip 5629 of the braid layer5609 can include an annular ring 5601 z therearound. In someembodiments, the ring 5601 z can be formed by melting the tips of thestrands 5633. In other embodiments, the ring 5601 z can be a separateelement that is bonded to the strands 5633 (e.g., bonded to less than20%, less than 10%, or less than 5% of the strands 5633). In someembodiments, there can be two bonding positions approximately 180degrees apart from one another. The ring 5601 z can advantageouslyensure that the strands 5633 do not unwind and yet can substantiallymove relative to one another underneath the ring 5601 z. The ring 5601 zcan be made, for example, of rubber, Kapton, PTFE, silicone, urethane,latex, or ePTFE.

As another example, as shown in FIG. 6C, the tip 5629 of the braid layer5609 can have a varying pick count along the tip 5629 with a greaterpick count at the tip and a lower pick count towards the center. As aresult, the strands 5633 can have a greater angle relative to thelongitudinal axis at the tip 5629 than in the rest of the layer 5609.For example, while the strands 5633 in the central portion of the device5600 can have an angle of 45° or less relative to the longitudinal axisof the device 5600 (for example, 40 degrees or less, 35 degrees or less,25 degrees or less, or 20 degrees or less), the strands 5633 at the tip5629 can have an angle of greater than 45°, such as between 45° and 60°,relative to the longitudinal axis (for example, 35 degrees, 45 degrees,or 55 degrees). The change in braid angle can be a continuous change atthe tip 5629 and/or can be created by joining two separate braidstogether. The strands 5633 of greater angle can be glued down to theinnermost layer at the tip 5629. By having a braid with a greater angleat the tip 5629, the tip 5629 can remain flexible as it curves or bendseven when the strands 5633 are fixed to the inner layer 5615. In someembodiments, the increasing braid angle at the tip 5629 can be createdby changing the speed of pulling the core inside the tubular braidduring manufacturing.

As another example, as shown in FIG. 6D, the tip 5629 of the braid layer5609 can be everted and bonded to the innermost layer 5615 (and/or otherlayer that is radially inwards of the braid layer 5609). The tip 5629can be more flexible relative to a non-everted tip 5629 because itincludes an extra (everted) length within which to allowed the strands5633 to move.

In some embodiments, the proximal and distal ends of the braid layer5609 can have different treatments (e.g., the distal end may have afirst treatment as described in FIGS. 6A-6D while the proximal end mayhave a second treatment as described in FIGS. 6A-6D).

In some embodiments, the rigidizing devices described herein (e.g.,rigidizing device 300) can include one or more slip layers bordering thebraid layer (e.g., braid layer 209). The slip layer can be configured toreduce friction between the braid and the bordering layers to allow thebordering layers (and in particular the braid layer) to more easilyshear or move relative to each other, particularly when no vacuum orpressure is applied to the rigidizing device, to maximize flexibility inthe flexible configuration. The slip layer can advantageously enhancethe baseline flexibility of the rigidizing device to allow the layers tomove relative to one another. In one embodiment, the slip layer caninclude a powder, such as talcum or cornstarch. In particular, a powderslip layer can advantageously reduce friction without adding significantthickness to the device, thereby enhancing flexibility of the rigidizingdevice in the flexible configuration. The slip layer can be made of alow coefficient of friction material, such as a thin film fluoropolymer(FEP, Chemfilm, PTFE, with thicknesses from 2-50 microns). In oneembodiment, the slip layer can be a coating. In one embodiment, the sliplayer can be a slip additive added to an elastomer. In one embodiment,the slip layer can be a sheath of thin plastic film that is inherentlylubricious, such as low-density polyethylene (LDPE). In one embodiment,the slip layer can be made of a thin spiral-wrapped film, such at0.0005″ FEP or 0.00025″ Chemfilm (St. Gobain). In one embodiment, theslip layer can be made of a grease, oil or other liquid.

The rigidizing devices described herein can include an innermost layerconfigured to provide an inner surface against which the additionallayers (e.g., braid layer) can be consolidated, for example, when avacuum or pressure is applied within the walls of the rigidizing device.The layer can further provide a seal for the wall (i.e., can beleak-proof) and can be strong enough to provide resistance todiametrical collapse even during bending of the rigidizing device and/orcompression of the rigidizing device during rigidization. Referring toFIG. 7, in some embodiments, the innermost layer 8815 can include areinforcement element 8850 z or coil within a matrix 8851 z. Thereinforcement element 8850 z can be a continuous spiral coil or closedrings with gaps in between them (which may exhibit more resistance tocollapse than a spiral coil). Additionally, the inner layer 8815 caninclude an inner film 8852 z and an outer film 8853 z on one or bothsides thereof. In some embodiments, each of the elements 8853 z, 8852 z,8850 z/8851 z can have a thickness of 0.0002″-0.015″.

The reinforcement element 8850 z can be, for example, a metal wire, suchas a metal wire made of stainless steel, nitinol, or Tungsten. Thereinforcement element 8850 z can be, for example, a high strength fiber(e.g., Kevlar, Dyneema, Vectran, Technora, or carbon fiber). Thereinforcement element 8850 z can be, for example, a stent, a structurecut from a tube, or a braid. In some embodiments, the reinforcementelement 8850 z can be a round wire (e.g., 0.0005″-0.030″ in diameter,such as 0.001″, 0.003″, 0.005″, 0.007″ or 0.009″ in diameter). In someembodiments, the reinforcement element 8850 z can be a rectangular wire(e.g., having a width of 0.001″ to 0.100″ inch, for instance, 0.010″,0.020″, 0.030″, 0.040″, 0.050″, 0.060″, 0.070″, 0.080″, 0.090″, or0.100″ and/or The rectangular wire can have a thickness from 0.0003″ to0.020″, for instance, 0.001″, 0.003″, 0.005″, 0.007″ or 0.010″). Inother embodiments, the reinforcement element 8850 z can have an ovalcross-section and/or can include a plurality of individual strandsand/or can have a rectangular cross section in which the four sharpcorners are rounded. In some embodiments, the reinforcement element 8850z can be cut from a single tube using, for instance, a laser to createthe gaps. In some embodiments, no reinforcement element is used.

In some embodiments, the reinforcement element 8850 z can be an elementwith a high aspect ratio (e.g., have a high RE width relative to REheight, such as an aspect ratio of over 5:1, such as over 10:1, such asover 11:1, such as approximately 12:1). Note that in FIG. 7, RE width isthe width of reinforcement element 8850 z, RE height is height orthickness of reinforcement element 8850 z, and RE Gap is distancebetween reinforcement elements 8850 z. The high ratio of width to heightof the reinforcement element 8850 z can advantageously help preventexternal pressure caused parallelogramming-type collapse of thereinforcement elements 8850 z within the innermost layer 8815.Parallelogramming-type collapse occurs when the spirals of the coil movefrom being approximately normal to the axis of the center of the coiltowards being parallel to the axis of the center of the coil (thespirals essentially “tip over”). Further, it may be advantageous inpreventing parallelogramming if the RE gap between the reinforcementelements 8850 z is no more than 3 times the RE height, such as no morethan 2 times the RE height, such as no more than 1.5 times the REheight. Additionally, a ratio of the inner diameter of a hollow tubewith an innermost layer 8815 to the width of the reinforcement layer8850 z in the innermost layer 8815 of less than 5, such as less than4.5, such as approximately 4.3, can likewise help preventparallelogramming-type collapse.

The matrix 8851 z may be a very low durometer, for example a TPU or TPE,with a durometer equal to or less than 60 A, 50 A, 40 A, 30 A, 20 A or10 A. In some embodiments, the matrix 8851 z can be TPU, TPE, PET, PEEK,Mylar, urethane, or silicone. Inner and outer films 8852 z, 8853 z cansimilarly include TPU, TPE, PET, PEEK, Mylar, urethane, or silicone. Insome embodiments, the inner and outer films 8852 z, 8853 z can beapplied by spraying, dipping, wrapping as a sheet or tube, pullingthrough a bath of solvent, melted, and/or consolidated. In someembodiments, the layer 8815 does not include inner and/or outer films8852 z, 8853 z and/or additional films can be included. The inner and/orouter films 8852 z, 8853 z can create a smooth inner and outer surface.

In a specific example of an innermost layer 8815 for a pressure system,the layer is made at 0.260″ inside diameter as a hollow tube with an REwidth of 0.050″, an RE height of 0.008″, and an RE Gap of 0.010″. Film8853 z is omitted on both sides. Film 8852 z (on both sides of thematrix 8851 z and reinforcement elements 8850 z) are all made ofurethane (600 psi to 100% strain). The thickness of both the matrix 8851z and each film 8852 z is about 0.006″, giving a total wall thickness of0.018″. This structure can resist collapse at over 10 atm of externalpressure.

In a second specific example of an innermost layer 8815 for a pressuresystem, film 8853 z is omitted on both sides. The RE width is 0.050″,the RE height is 0.008″, and the RE Gap is 0.010″. The film 8852 z is ahigher durometer elastomer, for example an elastomer that has a stressof 2000 psi@100% strain and has a thickness of about 0.001″ thick. Thematrix 8851 z can be an 50A urethane. The matrix 8851 z can be depositedas thermoplastic elastomer cord stock, for example at 0.008″ rectangularcross section or 0.010″ round cross section. This cord stock can also bedeposited with increased axial modulus (but not transverse modulus) byco-extruding the stock with a wire (for example, 0.001″ diameter) orfiber at its core.

In a third specific example of an innermost layer 8815 for a pressuresystem, the reinforcement element 8850 z can be a wire with a highaspect ratio. For example, the layer 8815 can have an RE height of0.005″, an RE width of 0.060″ and an RE gap of 0.006″ in a squarestainless steel wire. The inner diameter of the tube formed with theinnermost layer 8815 is 0.26″. Elements 8852 z and 8851 z can be 80 Aurethane and can be approximately 0.002″ thick. Further, layer 8851 zcan be a 50 A urethane (e.g., deposited from a heated tank with meltedurethane therein and an orifice for precise dispensing via pressure).The structure of this exemplary innermost layer 8815 can resist collapseat over 10 atm of external pressure, such as over 12 atm of pressure,such as over 13 atm of pressure.

In a specific example of an innermost layer 8815 for a vacuum system,the outer film 8853 z on one side (e.g., the outer or top side) isomitted, the film 8852 z above (outside of) the reinforcement/matrixincludes a 0.005″ 50A urethane, the matrix 8851 z is made of 0.005″thick 50A urethane, the reinforcement element 8850 z is a stainlesssteel wire, the film 8852 z below (inside of) the reinforcement/matrixincludes 0.0025″ thick 50A urethane, and the bottom outer film 8853 z isa 0.004″ thick 80A urethane. The RE width is 0.020″, the RE height is0.005″, and the RE Gap is 0.010″. The bottom outer film 8853 z ishydrophilically coated. The inner diameter of the tube formed by layer8815 is 0.551″.

Although shown in FIG. 7 as symmetrical, it should be understood thatthe innermost layer 8815 need not have a symmetrical arrangement offilms 8852 z, 8853 z. For example, neither layer may be on the bottom(inside of the matrix/reinforcement) while both layers are present ontop. Additionally, it should be understood that the material for bothinnermost films 8852 z need not be the same, nor need the material forthe both of the outermost films 8853 z be the same.

The reinforcement elements of the innermost layer can be in a variety ofconfigurations. As shown in FIGS. 8D-8F, the reinforcement element 9205z can be a multi-start coil winding (e.g., 2 starts as shown in FIG. 8F,three starts as shown in FIG. 8E, or four starts as shown in FIG. 8D).When multi-start coil windings are used the gap between reinforcementelements along the longitudinal axis can be the same as with a singlecoil, but number of starts can be 2, 3, 4, 5, 6, 7, 8, 9 or even more.While a single start creates a wire angle that is nearly vertical (forexample, 2 degrees off of vertical), a multi-start approach creates awire angle that biases the coils to tilt in one direction, much furtheraway from vertical (for example, 4, 6, 10, 15, or even 20 degrees). Thislarger angle may serve to make the innermost layer less likely to tiltor structurally collapse under pressure, as the coils with the largerpitch tend to brace against one another for stability. FIGS. 8A-8C showindividual starts (coils) from the multistart reinforcement elements9205Z. FIG. 8C shows one coil from FIG. 8F, FIG. 8B shows one coil fromFIG. 8E and FIG. 8A shows one coil from FIG. 8D.

In some embodiments, referring to FIGS. 9A-9B, the reinforcementelements 8950 z can be a series of wavy or undulated wires (or anundulated wire that is coiled as described herein). As shown in FIG. 9B,when the device is loaded, the undulated reinforcement elements 8950 zmoves toward colliding with itself, compressing the matrix 8851Z inbetween the wires and resisting a parallelogram-type collapse. In onespecific embodiment, an innermost layer with such an undulating wire canhave an RE height of 0.005″, an RE width of 0.060″ and an RE gap of just0.006″. The undulating wave can vary +/−0.03″ from a centerline (thatis, have a wave amplitude of 0.060″). The wave can repeat every 0.3″(that is, have a wavelength of 0.3″).

In some embodiments, referring to FIGS. 10A-10C, the reinforcementelements 9050 z can include alternating pocket wires 9052 z and notchedwires 9053 z. When unloaded, the pockets and notches of each respectiveelement can be separate (as shown in FIG. 10D). However, when loaded,the notch of wire 9053 z moves toward colliding with the pocket of wire9052 z (as shown in FIG. 10E) compressing the matrix 8851 z in betweenthe wires and resisting a parallelogram-type collapse.

In some embodiments, referring to FIGS. 11A-11B, the reinforcingelements 9150 z can be a flexure design, e.g., cut from a laser tube.

In some instances, the reinforcement element can be separate from theinner layer. For instance, the reinforcement element can be positioneddiametrically inside or outside the inner layer. The innermost layer canhave a hardness, for example, of 30 A to 80 A. Further, the innermostlayer can have a wall thickness of between 0.0005″ and 0.060″. In someembodiments, the innermost layer can include lubrication or a coating(e.g., hydrophilic coating) on the inner surface thereof to improvesliding of an endoscope or other instrument therethrough. The coatingcan be hydrophilic (e.g., a Hydromer® coating or a Surmodics® coating)or hydrophobic (e.g., a fluoropolymer). The coating can be applied, forexample, by dipping, painting, or spraying the coating thereon. Theinnermost layer can be a laminated layer with a low frictionalcoefficient.

Exemplary rigidizing devices in the rigidized configuration are shown inFIGS. 12A and 12B. As the rigidizing device is rigidized, it does so inthe shape it was in before vacuum or pressure was applied, i.e., it doesnot straighten, bend, or otherwise substantially modify its shape (e.g.,it may stiffen in a looped configuration as shown in FIG. 12A or in aserpentine shape as shown in FIG. 12B). This can be because the airstiffening effect on the inner or outer layers (e.g., made of coil-woundtube) can be a small percentage (e.g., 5%) of the maximum loadcapability of the rigidizing device in bending, thereby allowing therigidizing device to resist straightening. Upon release of the vacuum orpressure, braids or strands can unlock relative to one another and againmove so as to allow bending of the rigidizing device. Again, as therigidizing device is made more flexible through the release of vacuum orpressure, it does so in the shape it was in before the vacuum orpressure was released, i.e., it does not straighten, bend, or otherwisesubstantially modify its shape. Thus, the rigidizing devices describedherein can transition from a flexible, less-stiff configuration to arigid configuration of higher stiffness by restricting the motionbetween the strands of braid (e.g., by applying vacuum or pressure).

The rigidizing devices described herein can toggle between the rigid andflexible configurations quickly, and in some embodiments with anindefinite number of transition cycles. As interventional medicaldevices are made longer and inserted deeper into the human body, and asthey are expected to do more exacting therapeutic procedures, there isan increased need for precision and control. Selectively rigidizingdevices (e.g., overtubes) as described herein can advantageously provideboth the benefits of flexibility (when needed) and the benefits ofstiffness (when needed). Further, the rigidizing devices describedherein can be used, for example, with classic endoscopes, colonoscopes,robotic systems, and/or navigation systems, such as those described inInternational Patent Application No. PCT/US2016/050290, filed Sep. 2,2016, titled “DEVICE FOR ENDOSCOPIC ADVANCEMENT THROUGH THE SMALLINTESTINE,” the entirety of which is incorporated by referenced herein.

The rigidizing devices described herein can be provided in multipleconfigurations, including different lengths and diameters. In someembodiments, the rigidizing devices can include working channels (forinstance, for allowing the passage of typical endoscopic tools withinthe body of the rigidizing device), balloons, nested elements, and/orside-loading features.

Referring to FIGS. 13A-13D, in one embodiment, a tubular rigidizingdevice 100 can include a wall having a plurality of layers positionedaround the lumen 120 (e.g., for placement of an instrument or endoscopetherethrough). A vacuum can be supplied between the layers to rigidizethe rigidizing device 100.

The innermost layer 115 can be configured to provide an inner surfaceagainst which the remaining layers can be consolidated, for example,when a vacuum is applied within the walls of the rigidizing device 100.The structure can be configured to minimize bend force/maximizeflexibility in the non-vacuum condition. In some embodiments, theinnermost layer 115 can include a reinforcement element 150 z or coilwithin a matrix, as described above.

The layer 113 over (i.e., radially outwards of) the innermost layer 115can be a slip layer.

The layer 111 can be a radial gap (i.e., a space). The gap layer 111 canprovide space for the braided layer(s) thereover to move within (when novacuum is applied) as well as space within which the braided or wovenlayers can move radially inward (upon application of vacuum).

The layer 109 can be a first braid layer including braided strands 133similar to as described elsewhere herein. The braid layer can be, forexample, 0.001″ to 0.040″ thick. For example, a braid layer can be0.001″, 0.003″, 0.005″, 0.010″, 0.015″, 0.020″, 0.025″ or 0.030″ thick.

In some embodiments, as shown in FIG. 13B, the braid can have tensile orhoop fibers 137. Hoop fibers 137 can be spiraled and/or woven into abraid layer. Further, the hoop fibers 137 can be positioned at 2-50,e.g., 20-40 hoops per inch. The hoop fibers 137 can advantageouslydeliver high compression stiffness (to resist buckling or bowing out) inthe radial direction, but can remain compliant in the direction of thelongitudinal axis 135 of the rigidizing device 100. That is, ifcompression is applied to the rigidizing device 100, the braid layer 109will try to expand in diameter as it compresses. The hoop fibers 137 canresist this diametrical expansion and thus resist compression.Accordingly, the hoop fiber 137 can provide a system that is flexible inbending but still resists both tension and compression.

The layer 107 can be another radial gap layer similar to layer 111.

In some embodiments, the rigidizing devices described herein can havemore than one braid layer. For example, the rigidizing devices caninclude two, three, or four braid layers. Referring to FIG. 13C, thelayer 105 can be a second braid layer 105. The second braid layer 105can have any of the characteristics described with respect to the firstbraid layer 109. In some embodiments, the braid of second braid layer105 can be identical to the braid of first braid layer 109. In otherembodiments, the braid of second braid layer 105 can be different thanthe braid of the first braid layer 109. For example, the braid of thesecond braid layer 105 can include fewer strands and have a larger braidangle α than the braid of the first braid layer 109. Having fewerstrands can help increase the flexibility of the rigidizing device 100(relative to having a second strand with equivalent or greater number ofstrands), and a larger braid angle α can help constrict the diameter ofthe of the first braid layer 109 (for instance, if the first braid layeris compressed) while increasing/maintaining the flexibility of therigidizing device 100. As another example, the braid of the second braidlayer 105 can include more strands and have a larger braid angle α thanthe braid of the first braid layer 109. Having more strands can resultin a relatively tough and smooth layer while having a larger braid angleα can help constrict the diameter of the first braid layer 109.

The layer 103 can be another radial gap layer similar to layer 111. Thegap layer 103 can have a thickness of 0.0002-0.04″, such asapproximately 0.03″. A thickness within this range can ensure that thestrands 133 of the braid layer(s) can easily slip and/or bulge relativeto one another to ensure flexibility during bending of the rigidizingdevice 100.

The outermost layer 101 can be configured to move radially inward when avacuum is applied to pull down against the braid layers 105, 109 andconform onto the surface(s) thereof. The outermost layer 101 can be softand atraumatic and can be sealed at both ends to create a vacuum-tightchamber with layer 115. The outermost layer 101 can be elastomeric,e.g., made of urethane. The hardness of the outermost layer 101 can be,for example, 30 A to 80 A. Further, the outermost layer 101 can be havea thickness of 0.0001-0.01″, such as approximately 0.001″, 0.002, 0.003″or 0.004″. Alternatively, the outermost layer can be plastic, including,for example, LDPE, nylon, or PEEK.

In some embodiments, the outermost layer 101 can, for example, havetensile or hoop fibers 137 extending therethrough. The hoop fibers 137can be made, for example, of aramids (e.g., Technora, nylon, Kevlar),Vectran, Dyneema, carbon fiber, fiber glass or plastic. Further, thehoop fibers 137 can be positioned at 2-50, e.g., 20-40 hoops per inch.In some embodiments, the hoop fibers 137 can be laminated within anelastomeric sheath. The hoop fibers can advantageously deliver higherstiffness in one direction compared to another (e.g., can be very stiffin the hoop direction, but very compliant in the direction of thelongitudinal axis of the rigidizing device). Additionally, the hoopfibers can advantageously provide low hoop stiffness until the fibersare placed under a tensile load, at which point the hoop fibers cansuddenly exhibit high hoop stiffness.

In some embodiments, the outermost layer 101 can include a lubrication,coating and/or powder (e.g., talcum powder) on the outer surface thereofto improve sliding of the rigidizing device through the anatomy. Thecoating can be hydrophilic (e.g., a Hydromer® coating or a Surmodics®coating) or hydrophobic (e.g., a fluoropolymer). The coating can beapplied, for example, by dipping, painting, or spraying the coatingthereon.

The innermost layer 115 can similarly include a lubrication, coating(e.g., hydrophilic or hydrophobic coating), and/or powder (e.g., talcumpowder) on the inner surface thereof configured to allow the borderinglayers to more easily shear relative to each other, particularly when novacuum is applied to the rigidizing device 100, to maximize flexibility.

In some embodiments, the outermost layer 101 can be loose over theradially inward layers. For instance, the inside diameter of layer 101(assuming it constitutes a tube) may have a diametrical gap of 0″-0.200″with the next layer radially inwards (e.g., with a braid layer). Thismay give the vacuum rigidized system more flexibility when not undervacuum while still preserving a high rigidization multiple. In otherembodiments, the outermost layer 101 may be stretched some over the nextlayer radially inwards (e.g., the braid layer). For instance, thezero-strain diameter of a tube constituting layer 101 may be from0-0.200″ smaller in diameter than the next layer radially inwards andthen stretched thereover. When not under vacuum, this system may haveless flexibility than one wherein the outer layer 101 is looser.However, it may also have a smoother outer appearance and be less likelyto tear during use.

In some embodiments, the outermost layer 101 can be loose over theradially inward layers. A small positive pressure may be appliedunderneath the layer 101 in order to gently expand layer 101 and allowthe rigidizing device to bend more freely in the flexible configuration.In this embodiment, the outermost layer 101 can be elastomeric and canmaintain a compressive force over the braid, thereby impartingstiffness. Once positive pressure is supplied (enough to nominallyexpand the sheath off of the braid, for example, 2 psi), the outermostlayer 101 is no longer is a contributor to stiffness, which can enhancebaseline flexibility. Once rigidization is desired, positive pressurecan be replaced by negative pressure (vacuum) to deliver stiffness.

A vacuum can be carried within rigidizing device 100 from minimal tofull atmospheric vacuum (e.g., approximately 14.7 psi). In someembodiments, there can be a bleed valve, regulator, or pump control suchthat vacuum is bled down to any intermediate level to provide a variablestiffness capability. The vacuum pressure can advantageously be used torigidize the rigidizing device structure by compressing the layer(s) ofbraided sleeve against neighboring layers. Braid is naturally flexiblein bending (i.e. when bent normal to its longitudinal axis), and thelattice structure formed by the interlaced strands distort as the sleeveis bent in order for the braid to conform to the bent shape whileresting on the inner layers. This results in lattice geometries wherethe corner angles of each lattice element change as the braided sleevebends. When compressed between conformal materials, such as the layersdescribed herein, the lattice elements become locked at their currentangles and have enhanced capability to resist deformation uponapplication of vacuum, thereby rigidizing the entire structure inbending when vacuum is applied. Further, in some embodiments, the hoopfibers through or over the braid can carry tensile loads that help toprevent local buckling of the braid at high applied bending load.

The stiffness of the rigidizing device 100 can increase from 2-fold toover 30-fold, for instance 10-fold, 15-fold, or 20-fold, whentransitioned from the flexible configuration to the rigid configuration.In one specific example, the stiffness of a rigidizing device similar torigidizing device 100 was tested. The wall thickness of the testrigidizing device was 1.0 mm, the outer diameter was 17 mm, and a forcewas applied at the end of a 9.5 cm long cantilevered portion of therigidizing device until the rigidizing device deflected 10 degrees. Theforced required to do so when in flexible mode was only 30 grams whilethe forced required to do so in rigid (vacuum) mode was 350 grams.

In some embodiments of a vacuum rigidizing device 100, there can be onlyone braid layer. In other embodiments of a vacuum rigidizing device 100,there can be two, three, or more braid layers. In some embodiments, oneor more of the radial gap layers or slip layers of rigidizing device 100can be removed. In some embodiments, some or all of the slip layers ofthe rigidizing device 100 can be removed.

The braid layers described herein can act as a variable stiffness layer.The variable stiffness layer can include one or more variable stiffnesselements or structures that, when activated (e.g., when vacuum isapplied), the bending stiffness and/or shear resistance is increased,resulting in higher rigidity. Other variable stiffness elements can beused in addition to or in place of the braid layer. In some embodiments,engagers can be used as a variable stiffness element, as described inInternational Patent Application No. PCT/US2018/042946, filed Jul. 19,2018, titled “DYNAMICALLY RIGIDIZING OVERTUBE,” the entirety of which isincorporated by reference herein. Alternatively or additionally, thevariable stiffness element can include particles or granules, jamminglayers, scales, rigidizing axial members, rigidizers, longitudinalmembers or substantially longitudinal members.

In some embodiments, the rigidizing devices described herein canrigidize through the application of pressure rather than vacuum. Forexample, referring to FIGS. 14A-14B, the rigidizing device 2100 can besimilar to rigidizing device 100 except that it can be configured tohold pressure (e.g., of greater than 1 atm) therein for rigidizationrather than vacuum. The rigidizing device 2100 can thus include aplurality of layers positioned around the lumen 2120 (e.g., forplacement of an instrument or endoscope therethrough). The rigidizingdevice 2100 can include an innermost layer 2115 (similar to innermostlayer 115), a slip layer 2113 (similar to slip layer 113), a pressuregap 2112, a bladder layer 2121, a gap layer 2111 (similar to gap layer111), a braid layer 2109 (similar to braid layer 109) or other variablestiffness layer as described herein, a gap layer 2107 (similar to layer107), and an outermost containment layer 2101.

The pressure gap 2112 can be a sealed chamber that provides a gap forthe application of pressure to layers of rigidizing device 2100. Thepressure can be supplied to the pressure gap 2112 using a fluid or gasinflation/pressure media. The inflation/pressure media can be water orsaline or, for example, a lubricating fluid such as soil or glycerin.The lubricating fluid can, for example, help the layers of therigidizing device 2100 flow over one another in the flexibleconfiguration. The inflation/pressure media can be supplied to the gap2112 during rigidization of the rigidizing device 2100 and can bepartially or fully evacuated therefrom to transform the rigidizingdevice 2100 back to the flexible configuration. In some embodiments, thepressure gap 2112 of the rigidizing device 2100 can be connected to apre-filled pressure source, such as a pre-filled syringe or a pre-filledinsufflator, thereby reducing the physician's required set-up time.

The bladder layer 2121 can be made, for example, of a low durometerelastomer (e.g., of shore 20 A to 70 A) or a thin plastic sheet. Thebladder layer 2121 can be formed out of a thin sheet of plastic orrubber that has been sealed lengthwise to form a tube. The lengthwiseseal can be, for instance, a butt or lap joint. For instance, a lapjoint can be formed in a lengthwise fashion in a sheet of rubber bymelting the rubber at the lap joint or by using an adhesive. In someembodiments, the bladder layer 2121 can be 0.0002-0.020″ thick, such asapproximately 0.005″ thick. The bladder layer 2121 can be soft,high-friction, stretchy, and/or able to wrinkle easily. In someembodiments, the bladder layer 2121 is a polyolefin or a PET. Thebladder 2121 can be formed, for example, by using methods used to formheat shrink tubing, such as extrusion of a base material and then wallthinning with heat, pressure and/or radiation. When pressure is suppliedthrough the pressure gap 2112, the bladder layer 2121 can expand throughthe gap layer 2111 to push the braid layer 2109 against the outermostcontainment layer 2101 such that the relative motion of the braidstrands is reduced.

The outermost containment layer 2101 can be a tube, such as an extrudedtube. Alternatively, the outermost containment layer 2101 can be a tubein which a reinforcing member (for example, metal wire, including roundor rectangular cross-sections) is encapsulated within an elastomericmatrix, similar to as described with respect to the innermost layer forother embodiments described herein. In some embodiments, the outermostcontainment layer 2101 can include a helical spring (e.g., made ofcircular or flat wire), and/or a tubular braid (such as one made fromround or flat metal wire) and a thin elastomeric sheet that is notbonded to the other elements in the layer. The outermost containmentlayer 2101 can be a tubular structure with a continuous and smoothsurface. This can facilitate an outer member that slides against it inclose proximity and with locally high contact loads (e.g., a nestedconfiguration as described further herein). Further, the outer layer2101 can be configured to support compressive loads, such as pinching.Additionally, the outer layer 2101 (e.g., with a reinforcement elementtherein) can be configured to prevent the rigidizing device 2100 fromchanging diameter even when pressure is applied.

Because both the outer layer 2101 and the inner layer 2115 includereinforcement elements therein, the braid layer 2109 can be reasonablyconstrained from both shrinking diameter (under tensile loads) andgrowing in diameter (under compression loads).

By using pressure rather than vacuum to transition from the flexiblestate to the rigid state, the rigidity of the rigidizing device 2100 canbe increased. For example, in some embodiments, the pressure supplied tothe pressure gap 2112 can be between 1 and 40 atmospheres, such asbetween 2 and 40 atmospheres, such as between 4 and 20 atmospheres, suchas between 5 and 10 atmospheres. In some embodiments, the pressuresupplied is approximate 2 atm, approximately 4 atmospheres,approximately 5 atmospheres, approximately 10 atmospheres, approximately20 atmospheres. In some embodiments, the rigidizing device 2100 canexhibit change in relative bending stiffness (as measured in a simplecantilevered configuration) from the flexible configuration to the rigidconfiguration of 2-100 times, such as 10-80 times, such as 20-50 times.For example, the rigidizing device 2100 can have a change in relativebending stiffness from the flexible configuration to the rigidconfiguration of approximately 10, 15, 20, or 25, 30, 40, 50, or over100 times. FIG. 15 shows a graph of bending strength vs pressure for arigidizing device as described herein. As shown, the bending strength ofthe rigidizing device increases as the pressure supplied to the wallincreases.

Simplified versions of a wall of various pressurized rigidizing devicessimilar to rigidizing device 2100 are shown in FIGS. 16A-16O. Forexample, rigidizing device 2200 a of FIG. 16A includes the innermostlayer 2215 a, pressure gap 2212 a, bladder layer 2221 a that is sealedto the outermost layer 2201 a, braid layer 2209 a, and outer containmentlayer 2201 a (similar as described with respect to rigidizing device2100). The rigidizing device 2200 a further includes end caps 2292 a atthe proximal and distal ends thereof to seal the pressure therein. Whenpressure is supplied to the pressure gap 2212 a via inlet 2293 a, thebladder layer 2221 a is pressed against the braid layer 2209 a, which inturn is pressed against the outermost layer 2201 a, preventing thestrands of the braid from moving relative to one another.

Referring to FIG. 16J, rigidizing device 2200 j is similar to rigidizingdevice 2200 a except that slip layer 2213 j and stiffening layer 2298 jare added. Layer 2213 j can be a slip layer as described herein, forexample comprising a coating film or powder. Layer 2298 j can be astiffening layer that, similar to layers 2201 j and 2215 j, can includea reinforcement element 2250 z as described elsewhere herein. Theadditional stiffening layer 2298 j can work in concert with the innerlayer 2215 j. For example, the two layers 2215 j and 2298 j can easilyslip past one another (via slip layer 2213 j) in the flexibleconfiguration and stick to one another to form a stiff compositestructure in the rigid configuration (i.e., when pressure is applied).Layer 2298 j can be a high durometer elastomeric rubber, for example aTPU or TPE with a durometer greater than or equal to 60 A, 70 A, 80 A or90 A. When the tube is in a flexible state, layers 2215 j and 2298 j mayeasily shear or move with respect to each other (e.g., due to slip layer2213 j) such that the flexibility of the system is lower than it wouldbe if the layers were bonded together. When the tube is in a rigid state(for example, when pressure is applied), layers 2215 j, 2298 j and 2213j may lock to each other and act like a single bonded layer in order toresist collapse of the wall of the rigidizing device 2200 j. Similar toother embodiments, the braid layer 2205 j can push against the outerlayer 2201 j when pressure is supplied to gap 2212 j to rigidize thedevice 2200 j.

Referring to FIG. 16B, rigidizing device 2200 b is similar to rigidizingdevice 2200 a except that the pressure gap 2212 b is surrounded by aneverted bladder layer 2221 b (or a double-layered bladder), i.e., suchthat the bladder layer 2221 b includes one side that borders the braidlayer 2205 b and one side that borders the innermost layer 2215 b. Aspressure is supplied to the pressure gap 2212 b (inside of the two sidesof the bladder layer 2221 b), the bladder layer 2221 b can expand bothagainst the innermost layer 2215 b and against the braid 2209 b (whichin turn can be pushed against the outermost layer 2201 b).

Referring to FIG. 16C, rigidizing device 2200 c is similar to rigidizingdevice 2200 a except that the bladder layer 2221 c is sealed to theinnermost layer 2215 c rather than the outermost layer 2201 c. Whenpressure is supplied to the pressure gap 2212 c via inlet 2293 c, thebladder layer 2221 c is pressed against the braid layer 2209 c, which inturn is pressed against the outermost layer 2201 c.

Referring to FIG. 16D, rigidizing device 2200 d is similar to rigidizingdevice 2200 b except that the innermost layer 2215 d is a spring elementrather than a coil-wound tube. Because the pressure is in the evertedbladder layer 2221 d, the inner layer 2215 d need not be sealed itself.

Referring to FIG. 16E, rigidizing device 2200 e is similar to rigidizingdevice 2200 a except that the innermost layer 2215 a is replaced with aninner payload 2294 e that is sealed at both the proximal and distal endsand can include a plurality of lumens therein (e.g., a working channel2291 e, a pressure channel 2292 e, and a rinse channel 2293 e).

Referring to FIG. 16F, rigidizing device 2200 f is similar to rigidizingdevice 2200 a except that the braid layer 2209 f is inside of thepressure gap 2212 f and the bladder layer 2221 f such that pressuresupplied to the pressure gap 2212 f causes the bladder layer 2221 f topush inwards against the braid layer 2209 f, which in turn pushesagainst innermost layer 2215 f.

In some embodiments, a pressure rigidizing device can include two braidlayers (e.g., of the same or different braid characteristics). Forexample, an exemplary rigidizing device 2200 m with two braid layers2209 m and 2205 m is shown in FIG. 16M. The two braid layers 2209 m and2205 m sandwich two bladders 2221 m and 2217 m (and/or a single annularbladder) therebetween. When pressure is supplied to the pressure gap2212 m between the two bladders, the outer braid layer 2205 m will bepushed radially outwards against the outer layer 2201 m while the innerbraid layer 2209 m will be pushed radially inwards against the innerbraid layer 2215 m to rigidize the device 2200 m.

Another exemplary rigidizing device 2200 n with two braid layers 2209 n,2205 n is shown in FIG. 16N. The two braid layers 2209 n, 2205 n arepositioned adjacent to one another between the bladder layer 2221 n (notlabeled in figure) and the outer tube 2201 n. When pressure is suppliedto the pressure gap 2212 n, the bladder 2221 n forces the two braidlayers 2209 n, 2205 n together and against the outer tube 2201 n. Thebraid layers 2209 n, 2205 n may interdigitate with one another whenpressurized, thereby strengthening the rigidity of the device 2200 n.

Referring to FIG. 16K, rigidizing device 2200 k is similar to rigidizingdevice 2200 a except that an annular ring 2219 k, e.g., including fibersand adhesive, is positioned around each of the ends of the braid layer2209 k and bladder layer 2221 k to attach the bladder layer 2221 k tothe innermost layer 2215 k (and thereby hold pressure within thepressure gap 2212 k when pressure is supplied through the inlet 2293 k).The annular ring 2219 k can, for example, include a high strength fiber,such as Kevlar or Dyneema. Further, the adhesive can be, for example, acyanoacrylate. In some embodiments, adhesive can also be placed at theends between the innermost layer 2215 k and the bladder layer 2221 k andalso encompassing the inlet tube.

FIG. 16G shows a rigidizing device 2200 g with gap inlet 2293 g and ventinlet 2223 g. Inlet 2293 g connects to pressure gap 2212 g (via pressureline 2294 g). Inlet 2223 g connects to gap 2206 g around the braid layer2209 g (between bladder 2221 g and outermost layer 2201 g). The device2200 g can be rigidized in one or more different configurations. In afirst rigidizing configuration, pressure can be applied to inlet 2293 gwhile the vent inlet 2223 g can be open or vented to atmosphericpressure. The pressure supplied to the pressure gap 2212 g through theinlet 2293 g can thus push the braid 2209 g against the outermost layer2201 g, which in turn can force any air in the gap 2206 g out throughthe vent inlet 2223 g. Allowing the air to escape through the vent inlet2223 g can enable a tighter mechanical fit between the braid layer 2209g and the outer layer 2201 g, thereby strengthening the rigidization ofthe device 2200 g. In a second rigidizing configuration, pressure can beapplied to inlet 2293 g and a vacuum can be applied to vent inlet 2223g. This may cause the rigidizing device 2200 g to become even stifferthan in the first configuration, as the vacuum can assist in moving thebraid layer 2209 g towards the outer layer 2201 g. The device 2200 g canlikewise be made flexible in one or more different configurations. In afirst flexible configuration, both inlet 2293 g and vent inlet 2223 gcan be opened to atmospheric pressure. This will loosen the braid layer2209 g relative to the outer layer 2201 g and cause the rigidizingdevice 2200 g to be flexible as the braid layer 2209 g moves freelyrelative to the outer layer 2201 g. In a second flexible configuration,a low pressure (e.g., 5-10% above atmospheric pressure) can be providedto both inlet 2293 g and vent inlet 2223 g. This may cause the outermostlayer 2201 g and the innermost layer 2215 g to separate slightly, whichcan provide additionally area for the braid layer 2209 g to move freely.As a result, this may cause the rigidizing device 2200 g to become evenmore flexible than in the first rigidizing configuration. Additionally,providing a low pressure above atmospheric pressure in the flexibleconfiguration can allow the rigidizing device 2200 g to be introducedinto the body with a very small diameter (e.g., such that the pressuregap 2212 g is essentially zero) and then the low pressure can beprovided to both inlet 2293 g and vent inlet 2223 g to slightly expandthe pressure gap 2212 g to provide more room for the braid layer 2209 gto move freely.

FIG. 16H shows a rigidizing device 2200 h with bellows 2243 h connectedto pressure line 2294 h. Pressure gap 2212 h, pressure line 2294 h, andbellows 2243 h can all be configured to be filled with a sealed pressuretransmitting medium, such as distilled water or saline solution or anoil. The pressure transmitting medium may be a radiopaque fluid thatadvantageously will show the rigidized device more clearly during aprocedure using fluoroscopy. The pressure transmitting medium can beadded to the rigidizing device immediately before use and/or when thedevice is being manufactured. In use, activating the actuator 2288 h cancompress bellows 2243 h, thus reducing the volume of pressure medium inthe bellows 2243 h, which flows through the pressure line 2294 h to thepressure gap 2212 h, causing a rise in pressure in the pressure gap 2212h and movement of the braid layer 2209 h against the outer layer 2201 h.The vent inlet 2223 h can be open to the atmosphere to allow gas toescape from the space 2206 h around the braid layer 2209 h. Further,reversing the action of the actuator 2288 h can cause the pressure inthe pressure gap 2212 h to fall as the pressure medium moves back to thebellows 2243 h. Actuator 2288 h can be, for example, a solenoid, a voicecoil, a lead screw, a valve, or a rotary cam. In some embodiments, thepressure line 2294 h can be pinched or flattened to raise the pressurein pressure gap 2212 h rather than using bellows 2243 h.

FIG. 16I shows a rigidizing device 2200 i including sumps 2230 i and2228 i respectively. Sumps 2230 i and 2228 i may comprise a fluidmedium, such as water and a gaseous medium such as air. Pressure orvacuum or combinations thereof may be applied to inlets 2293 i, 2223 i.Using the sump configuration shown may mean that there is no air or gasin the rigidizing device regardless of the pressurization state of eachgap 2206 i or 2212 i (increased pressure, vacuum or atmosphericpressure). In the event that the gaps leaks during a procedure, this maymean that only the fluid medium enters into the patient. This may offerpatient protection from gaseous (e.g. air) embolization.

In some embodiments, the rigidizing devices described herein can includea plurality of individual bladders running longitudinally down thelength of the device. For example, referring to FIG. 16O, device 2200 oincludes four different circumferential bladders 2221 o surroundingpressure gaps 2212 o. In this embodiment, the braid layer is likewisedivided into four longitudinal flat braids 2209 o, each of which ispositioned radially outwards from a bladder 2221 o. In otherembodiments, the braid layer can include tubular braids wrapped aroundthe bladders 2221 o (similar to as described with respect to FIG. 67below). Further, the outer and inner layers 2201 o, 2215 o are connectedby dividers 2236 o. In some embodiments, the dividers 2236 o can beformed by elements of the outer or inner layers 2201 o, 2215 o (e.g., becontinuous elements of one or both layers 2201 o, 2215 o). In someembodiments, the dividers 2236 o can be configured to help maintain thethickness of the wall. When pressure is supplied to the pressure gaps2212 o, the bladders 2221 o expand to push the flat braids 2209 oagainst the outer layer 2201 o.

In some embodiments, referring to FIG. 16L, the pressure rigidizingdevices described herein do not include an innermost layer (e.g., do notinclude an innermost layer with a reinforcement element therein).Rather, the rigidizing device 2200 l can include an outer layer 2201 l,gap layer 2206 l, braid layer 2209 l, and an everted or tubular bladder2221 l (with a pressure gap 2212 l therein). The tubular bladder 2221 lcan be configured to be positioned around the inner device (such as ascope 2291). As the pressure gap 2212 l is filled with pressurizingmedium, the bladder 2221 l can expand against the scope 2291 and thebraid layer 2209 l. It should be understood that any of the featuresdescribed herein with respect to vacuum rigidizing devices can besubstituted or replaced with any of the features described with respectto pressure rigidizing devices.

In some embodiments, the rigidizing devices described herein canincorporate a tool or working channel therein. The working channel canbe designed so as to not significantly add to the rigidizing device'sbending stiffness. Referring to FIGS. 17A-17C, in one embodiment, arigidizing device 500 can include a working channel 555 extendingtherethrough. The working channel 555 can include a central lumen 571 z(e.g., for passage of a working element therethrough) formed byalternating telescoping tubular sections that are locally necked ortapered from a larger diameter end 569 z to a smaller diameter end 570z. Each of the sections can be connected to the underlying layer of thewall (e.g., the slip layer 513 over the innermost layer 515) at adiscrete location or anchor point 568 z and can be otherwise free tomove. As the rigidizing device 500 bends, the smaller diameter end 570 zcan move within the larger diameter end 559 z of a neighboring sectionso as to allow for bending of the working channel 555. The workingchannel 555 can be positioned within the wall of the rigidizing device500, such as in the radial gap 511 between the slip layer 513 and thefirst braid layer 509 (and can therefore also be positioned underneaththe radial gap layer 507, the second braid layer 505, the radial gaplayer 503, and the outermost layer 501). The working channel 555 canthus be positioned within the sealed vacuum (or pressure chamber) of therigidizing device 500. In some embodiments, the working channel 555 canitself be positioned within a sealed bag or layer 572 z so as to ensurethat there is no vacuum or pressure leak path. In other embodiments, thesections can include sliding seals therebetween to ensure that there isno vacuum or pressure leak path. In some embodiments, as shown in FIG.17D, rather than having tapered sections, there can be alternative largediameter sections 525 a and small diameter sections 525 b. The smallerdiameter sections 525 b can move within the large diameter sections 525a during bending over the rigidizing device 500. The working channel canbe placed within the sealed volume formed by layers 501 and 515 or itcan be placed outside of this sealed volume, such as on top of layer501.

Referring to FIGS. 18A-18B, in some embodiments, a rigidizing device7800 can include a working channel 7855 spiraled around a portion of theelongate body 7803 z of the rigidizing device 7800. For example, theworking channel 7855 can be spiraled at a 40-50 degree angle, such asapproximately a 45 degree angle, relative to the longitudinal axis ofthe device 7800. A spiraled working channel 7855 can advantageouslydeform into a curved path as the rigidizing device 7800 bends withoutresisting bending and/or without forcing path length adjustments alongits length. The working channel 7855 can include a proximal port 7840 zintegrated into the handle 7831 and a distal port 7841 z (through whicha working tool may exit) molded onto end of the tip 7833 z of therigidizing device 7800. The spiraled working channel 7855 can bepositioned over the outermost layer 7801, under the outer layer 7801 (asshown in FIGS. 18A-18B where the outer layer 7801 has been removed forclarity), or further within the layers of the wall (.e., under the braidlayer).

Referring to FIGS. 19A-19B, in some embodiments, a rigidizing device4500 can include a plurality of working channels 4555 spiraled aroundthe outside thereof. As shown in FIGS. 19A-19B, the working channels4555 can, for example, form a spiral shield around the rigidizing device4500. In some embodiments, the working channels 4555 can be configuredtogether to form a second rigidizing element that can be rigidizedseparately from the inner rigidizing device 4500. The second rigidizingelement can advantageously be highly flexible due to the relativemovement of the individual spiraling working channels 4555. In someembodiments, the working channels 4555 can include a thin flexible ringand/or thin flexible sheath to contain the working channels 4555 in acircular cross section. In some embodiments, the device 4500 can furtherinclude a steerable distal tip 4547, e.g., to help with placement of thetools that extend through the working channels 4555.

Referring to FIGS. 20A-20B, in some embodiments, a rigidizing device8000 can include a rigidizing elongate body 8003 z with a plurality ofworking channels 8055 a-d (such as 1-10, 3-5, or 4-5 working channels)extending down the central lumen 8020 thereof to the tip 8033 z. Theworking channels 8055 a-d can be used for a plurality of different toolsthroughout a procedure. For example, one of the working channels 8055a-d can be used for a catheter with a camera and lighting, another couldbe used for traction, another could be used for cutting, another couldbe used for suction, etc. The elements extended down the workingchannels 8055 a-d can be interchanged throughout the procedure. In someembodiments, the rigidizing elongate body 8003 z can be disposable whilethe tools can be cleanable and/or sterilizable. In some embodiments, therigidizing device 8000 can further include passive or active linkages8004 z.

Referring to FIG. 21, in some embodiments, a rigidizing device 8100 caninclude a first working channel 8155 a and a second working channel 8155b. The first working channel 8155 b can extend down the central lumen8120 (or within the walls of the elongate body 8103 z) to the distal end8133 z. The second working channel can similarly extend down the centrallumen 8120 or within the walls of the elongate body 8103 z, but can exitthe side of the elongate body 8103 z proximal to the distal section 8102z (e.g., prior to the linkages 8104 z). Having tool channel 8155 b exitproximal to the distal section can advantageously limit interferencewith steering or bending of the linkages 8104 z.

Referring to FIG. 22, in some embodiments, a tool 7942 z can bespecifically designed for use with a working channel of a rigidizingdevice as described herein. The tool 7942 z can include a flexible shaft7943 z and an expandable atraumatic tip 7944 z. The atraumatic tip 7944z can be an expandable balloon or a nitinol cage with foam therearound.In some embodiments, the expandable tip 7944 z can be configured to becollapsed (e.g., sheathed) for delivery through the working channel andto self-expand after sheath withdrawal and placement through the workingchannel. The atraumatic tip 7944 z can be sized, for example, so as tonot fill the lumen of the gastrointestinal tract and therefore so as tonot contact the walls of the gastrointestinal tract. The tool 7942 z canfurther have a flexible loop 7945 z that is attached to the tip 7944 zor to the shaft 7943 z. In some embodiments, the loop 7945 z can beattached to an endoscopic clip (often used to close a variety of defectsin the GI tract) to provide traction during an ESD procedure. By slidingthe shaft 7943 z longitudinally, the user can provide traction to theclip. The expandable atraumatic tip 7944 z can advantageously allow thetool 7942 z to be advanced freely ahead of the rigidizing device withoutbeing concerned that it will cause trauma or get caught in the GI tract.By hooking the flexible loop 7945 z onto the clip, the tool 7942 z canget good traction with a simple back and forth motion of the flexibleshaft 7943 z.

Any of the rigidizing devices described herein can have a distal endsection or sections with a different design that the main elongate bodyof the rigidizing device. As shown in FIG. 23, for example, rigidizingdevice 5500 can have a main elongate body 5503 z and a distal endsection 5502 z. Only the distal end section 5502 z, only the mainelongate body 5503 z, or both the distal end section 5502 z and the mainelongate body 5503 z can be rigidizing as described herein (e.g., byvacuum and/or pressure). In some embodiments, one section 5502 z, 5503 zis activated by pressure and the other section 5502 z, 5503 z isactivated by vacuum. In other embodiments, both sections 5502 z, 5503 zare activated by pressure or vacuum, respectively.

Referring to FIG. 24, in some embodiments, the distal section 5702 z caninclude a rigidizing braid that differs from the braid of the mainelongate section 5703 z. For example, in one embodiment, the braid anglerelative to the longitudinal axis in the distal end section 5702 z canbe greater than the braid angle of the main elongate body 5703 z. Forinstance, the braid angle in distal section may be 40 degrees while thebraid angle in the main elongate body may be 20 degrees. The braids mayoverlap somewhat and be joined with a flexible adhesive. These designsmay give the distal end section 5702 z more bending flexibility in anon-rigidized state than the main elongate section 5703 z. Having a moreflexible distal tip can, for example, advantageously prevent bucklingand drag at the tip (caused by fixing the braid ends) and/or canadvantageously provide flexibility during navigation through a bodylumen to prevent trauma to the anatomy. In another embodiment, the braidangle relative to the longitudinal axis in the distal end section 5702 zcan be less than the braid angle of the main elongate body 5703 z. Thismay give distal end section 5702 z more stiffness in the rigidized staterelative to the main elongate body 5703 z. Having more stiffness in thedistal end section 5702 z can, for example, advantageously provide astable platform for movement or delivery of a medical device through thecentral lumen and out the distal end of the rigidizing device 5700.

Referring to FIG. 25, in some embodiments, the distal end section 5802 zcan include a plurality of linkages 5804 z that are passively activated.The linkages 5804 z can be connected together at one or more pivotpoints and can advantageously provide deterministic bending (i.e.,bending in a specific and predetermined direction). Additionally, thelinkages 5804 z can advantageously provide torsional rigidity to thedistal end section 5802 z while providing high flexibility for bending.The linkages 5804 z can be activated passively, e.g., via flexing as thedevice 5800 is moved through the anatomy. The distal end section 5802 zmay, for example, include 1-100 linkages 5804 z, such as 1, 2, 4, 6, 8,10, 16, 20, 30, or 40 links 5504 z. In some embodiments, the linkages5804 z can be formed by passively cut flexures, such as laser cut tubesor stents.

Referring to FIG. 26, in other embodiments, the distal end section 7602z can include a plurality of linkages 7604 z that are activelycontrolled, such as via cables 7624, for steering of the rigidizingdevice 7600. The device 7600 is similar to device 5800 except that itincludes cables 7624 configured to control movement of the device. Whilethe passage of the cables 7624 through the rigidizing elongate body 7603z (i.e., with outer wall 7601, braid layer 7609, and inner layer 7615)is not shown in FIG. 26, the cables 7624 can extend therethrough in anymanner as described elsewhere herein. In some embodiments, one or morelayers of the rigidizing elongate body 7603 z can continue into thedistal end section 7602 z. For example, and as shown in FIG. 26, theinner layer 7615 can continue into the distal end section 7602 z, e.g.,can be located radially inwards of the linkages 7604 z. Similarly, anyof the additional layers from the rigidizing proximal section (e.g., thebraid layer 7609 or the outer layer 7601 may be continued into thedistal end section 7602 z and/or be positioned radially inwards of thelinkages 7604 z). In other embodiments, none of the layers of therigidizing elongate body 7603 z continue into the distal end section7602 z. The linkages 7604 z (and any linkages described herein) caninclude a covering 7627 z thereover. The covering 7627 z canadvantageously make the distal end section 7602 z atraumatic and/orsmooth. The covering 7627 z can be a film, such as expanded PTFE.Expanded PTFE can advantageously provide a smooth, low friction surfacewith low resistance to bending but high resistance to buckling.

FIGS. 27A-E show another exemplary distal end section 4302 z thatincludes a plurality of linkages 4304 z that are actively controlled,such as via cables 4324, for steering of the rigidizing device. In someembodiments, the pivots for the linkages 4304 z can be involutes,similar to gear teeth, as shown in FIGS. 27A-E, to reduce the localcontact drag. The cables 4324 can be positioned within cable guides(e.g., jackets or coil pipes) that extend the length of the rigidizingdevice. In some embodiments, the cables 4324 (and cable guides) canextend within the wall of the rigidizing device. The cable guides canadvantageously ensure that tensile load is carried through the cableguide, rather than through the wall of the rigidizing device, so thatthe structure of the wall is not adversely deflected as the load isapplied to the linkages 4304 z. In some embodiments, the cable guidesand cables 4324 can have excess length to account for bending of therigidizing device. This excess length can, for example, be woven orcurled within the wall of the rigidizing device. Further, the cables4324 can run through apertures and/or grooves in the linkages 4304 z(see, e.g., FIG. 27C) while remaining otherwise free to float within thewall (and thereby to account for bending of the rigidizing device. Asthe cables 4324 are activated, the linkages 4304 z pivot relative to oneanother, thereby providing steering for the distal end section of arigidizing device. Articulation of the linkages 4304 z and cables 4324for steering can be achieved by actuators (e.g., local motors,current-activated (heat) nitinol wires, proximal actuators (typicallystainless steel, tungsten, or composites), hydraulics, and/or EAP(electro-active polymers)). Such steering mechanisms can advantageouslyprovide increased clinical utility. Further, such steering allows thedevice that is positioned through the central lumen (for example, anendoscope or a guidewire) be steered towards and more easily reach thedesired anatomical location.

When cables are used for steering the distal end section, the cables(which can be in cable guides or not) can be routed through the wall ofthe rigidizing devices described herein in a number of different ways.FIGS. 28-39B show exemplary configurations of rigidizing devices withcable guides (some wall layers have been omitted in FIGS. 28-39B forclarity). For example, FIG. 28 shows a rigidizing device 6200 havingcables 6224 extending in cable guides 6299 within the outer radial gaplayer 6207 (and thus between the braid layer 6209 and the outer layer6201). In some embodiments, each of the cables 6224 and cable guides6299 can be positioned approximately equidistant around thecircumference (i.e., approximately 90 degrees away from neighboringcables when four cables are used). In other embodiments, one or more ofthe cables 6224 and cable guides 6299 can be grouped closely together(e.g., within the same quadrant) rather than spaced apart. Further, insome embodiments, the cables 6224 and/or guides 6299 can beasymmetrically positioned around the circumference of the rigidizingdevice 6200.

FIG. 29 shows a rigidizing device 6300 in which the cables 6324 andcable guides 6399 are positioned within the inner radial gap layer 6311(and thus between the braid layer 6309 and the inner layers of therigidizing device, such as the bladder 6321). When, for example,pressure is supplied to pressure gap 6312, the bladder 6321 can pushagainst the braid layer 6309, and the braid layer and correspondinglypush against the outer layer 6301 without the braid layer 6309 squeezingor otherwise impacting the cables 6324. Again, the cables 6324 and cableguides can be positioned equidistant or asymmetrically about thecircumference of the rigidizing device 6300.

Referring to FIG. 30, in some embodiments, the rigidizing device 6400can have cables 6424 and cable guides 6499 at least partially separatedfrom the pressurized or vacuum zone. For example, as shown in FIG. 30, atubular bladder layer 6421 can surround the pressure gap 6412. Some orall of the cables 6424 and cable guides 6499 can be positioned in thegap 6407 between the inner layer 6415 and the braid layer 6409 andcircumferentially adjacent to the tubular bladder layer 6421.Advantageously, in this configuration, the cables 6424 and cable guides6499 can both be minimally impacted by pressurization of the bladderlayer 6421 and provide substantially no additive stack height orthickness to the wall.

Referring to FIG. 31, in some embodiments, the rigidizing device 6500can include a plurality of tubular bladders 6521 spacedcircumferentially apart such that each cable 6524 and cable guide 6599can fit in the gap 6507 between adjacent tubular bladders 6521.

Referring to FIG. 32, rigidizing device 6600 is similar to device 6500except that cables 6624 and guides 6699 are grouped in pairs to reducethe number of tubular bladders 6621 necessary (e.g., there can be twotubular bladders 6621 and a two pair of cables 6624 and guides 6699positioned therebetween).

Referring to FIG. 33, rigidizing device 6700 is similar to device 6500except that each tubular bladder 6721 includes a tubular braid layer6709 therearound (i.e., rather than having a single braid layer 6509 aswith device 6500). As pressurizing medium is provided to pressure gaps6712, the bladder 6721 can expand to press each individual tubular braid6709, which can expand to press against the inner and outer layers 6715,6701. Alternately, not all of the bladders can be pressurized at thesame time (for instance, just 1 or 2) such that the device is onlystiffened partway around the circumference. This may create stiffnessalong only a portion of the device, while still enabling flexibilityamongst the other portion, which may create preferential motion shouldthe device be imparted with a deflection load.

Referring to FIG. 34, in some embodiments, a rigidizing device 6800 caninclude strips of braid layer 6809 (i.e., flat braid rather than tubularbraid). Each strip of braid layer 6809 and each cable 6824 and cableguide 6899 can be positioned in the radial gap 6807. Further, the stripsof braid layer 6809 can alternate with the cables 6824/6899 so as tominimize the thickness of the wall of the rigidizing device 6800. Thebladder 6821 can be positioned radially outwards of the strips of braidlayer 6809 and cables 6824/guides 6899. When pressure medium is suppliedto the pressure gap 6812, the bladder 6821 can push the strips of braidlayer 6809 radially inwards against the innermost layer 6815 to rigidizethe device 6800. In other embodiments, the bladder 6821 can be radiallyinwards of the strips of braid layer 6809 (and cables 6824/guides 6899)and be configured to push the strips of braid layer 6809 against theouter layer 6801.

In some embodiments, referring to FIG. 35, the cables 6924 and cableguides 6999 can be positioned so as to extend down the central lumen6920 of the rigidizing device 6900.

In some embodiments, referring to FIG. 36, the cables 7024 and cableguides 7099 can be positioned radially outwards of the outer layer 7001.The cables 7024 and guides 7099 can, for example, be positioned in asheath 7009 z that can extend only over the cables 7024 or that canfully encompass the outer layer 7001. The guides 7099 can be onlyminimally constrained within the sheath 7009 z so as to freely bendduring movement of the device 7000 (e.g., so as to curl or extend tofull length depending on whether the guides 7099 are positioned on theinside or outside of the cure of the rigidizing device 7000 as itbends).

Referring to FIG. 37, in some embodiments, a cable guide 7199 (with oneor more cables therein) can be spiraled around the outside of the outerlayer 7101 of the rigidizing device 7100. Additional cable guides canlikewise be spiraled therearound. In some embodiments, the cable guide7199 can be spiraled around other layers of the rigidizing device 7100,such as around the inner layer.

Referring to FIGS. 38A-38B, in some embodiments, a cable guide 7299(with one or more cables therein) and a tubular element 7210 z can bealternately spiraled around the inner layer 7215 (i.e., such that thecable guide 7299 and the tubular element 7210 z form approximately asingle layer down the length of the rigidizing device 7200. The tubularelement 7210 z can include an outer tubular braid 7209 with an innertubular bladder 7221. As pressurizing medium is provided to pressure gap7212, the bladder 7221 can expand to press outwards on the tubular braid7209, which can push outwards on the outer layer (not shown forclarity).

Referring to FIGS. 39A-39B, a rigidizing device 7300 can be similar todevice 7200 except that only the cable guide 7399 and a tubular bladder7321 can be spiraled around the inner layer 7315 within gap 7311 (notethat cable guide 7399 and tubular bladder 7321 are not shown in FIG. 39Bfor clarity). A braid layer 7309 can then be wrapped radially around thegap 7311. When a pressure medium is supplied to the tubular bladder7321, the bladder 7321 can expand to push the braid layer 7309 againstthe outer layer 7301 (not shown in FIG. 39A for clarity).

It should be understood that the cable configurations described withrespect to FIGS. 28-39B can be used with any number of cables (such as1, 2, 3, 4, 5, 6, 8, 12, or 16 cables). Further, the cables can be usedto steer any tip or a rigidizing device and/or to steer any distal endsection (e.g., sections with linkages or different braid angles).Further, the cable guides described herein can be round with roundcables, flat, rectangular with flat ribbon tensile elements, or acombination thereof. Further, in some embodiments, other steeringelements can be used in addition to or in place of the cables (e.g.,pneumatics, hydraulics, shape memory alloys, EAP (electro-activepolymers), or motors). Intentionally separating the elements requiredfor steering and the elements required for rigidization can enable thestructure to exhibit a continuously high rigidization performance as afunction of length, even if the forces available for steering aredemonstrably lower than the forces required for nested systemrigidization.

Additionally, it should be understood that the cable configurations andplacement described with respect to FIGS. 28-39B can similarly be usedfor the placement of working channels or other lumens (for example,inflation lumens for balloons) within the rigidizing devices.

Referring to FIGS. 40A-40D, in some embodiments, the distal end section5902 z may include a series of linkages 5904 z (either active orpassive) that are specifically designed to rigidize via the applicationof pressure or vacuum. For example, the linkages 5904 z can be connectedto each other through a pivot point 5928 z (which can, for example, bewire pivot points). Each pivot point 5928 z can allow bending with onedegree of freedom between linkages. Further, the linkages 5904 z can bearranged in alternating fashion with every other linkage connected withthe pivot points 5928 z positioned 90 degrees away from the previouslinkage. Each linkage 5904 z can have cut-outs 5975 z at the proximaland distal ends thereof extending from the pivot-points 5928 z to as toallow bending of the linkages 5904 z relative to one another. Further,each linkage 5904 z can be connected to a neighboring linkage 5904 z bya respective tensile member 5930 z. The tensile member 5930 z can befixed relative to one linkage and at least partially movable within atrack 5931 z of the neighboring linkage (e.g., within track 5931 z oflinkage 5904 z). Movement of the linkages 5904 z allows the tensilemember 5930 z to lengthen when on the outside of the curve and shortenwhen on the inside of the curve during bending of the rigidizing device.Further, the proximal end section 5902 z can include two sliding clamps5932 z attached to tensile member 5930 z along opposite axis (i.e., 90degrees away from one another). The two tensile members 5930 z extendfrom each of the sliding clamps 5932 z to the distal-most end of thedistal section 5902 z. As the distal end section 5902 z is bent, onecable element of each sliding clamp 5932 z gets shorter and one cableelement of each sliding clamp 5932 z gets longer, resulting incircumferential movement of the sliding clamps 5932 z. When vacuum orpressure is applied, the outer sleeve can compress the sliding clamps5932 z to the track 5931 z surface. The sliding clamps 5932Z and thetrack 5931 z surface may be smooth, rough or have teeth. Thiscompression force may case the sliding clamps 5932Z to lock in placewith respect to the links 5904 z, thereby fixing the position of tensilemembers 5930 z and making the distal end section stiffer in its currentshape. Additional rigidizing linkages and/or engages are described inInternational Patent Application No. PCT/US2018/042946, filed Jul. 19,2018, titled “DYNAMICALLY RIGIDIZING OVERTUBE,” now PCT Publication No.WO 2019/018682, the entirety of which is incorporated by referenceherein.

Referring to FIGS. 41A-41B, in some embodiments, the distal end section6002 z can include linkages 6004 z (either active or passive) that areplaced over a section 6007 z that rigidizes via vacuum or pressure asotherwise described herein (i.e., over a rigidizing wall with innerlayer 6015, pressure gap 6012, bladder 6021, braid layer 6009, and outerlayer 6001). Placing the linkages 6004 z over the rigidizing section canprovide the advantages of a linked system (e.g., flexibility in bendingand torsional stiffness) together with a steering or deterministicbending tip that can be rigidized when the remaining structure isrigidized. Alternatively, linkages can be positioned radially inwards ofa rigidizing section. As shown in FIG. 41B, cables 6024 in cable guides6099 can extend through linkages 6004 z to provide optional activesteering of the linkages 6004 z.

Referring to FIG. 42A, in some embodiments, the distal end section 6102z can include a series of linkages 6104 z (either active or passive)sealed within a thin layer of material 6108 z(e.g., made of anelastomer, PVC, or PEEK). The linkages 6104 z and thin layer of material6108 z can, for example, be positioned over (i.e., radially outwardsfrom) the braid layer 6109 and can be continuous with the coil woundtube 6101 of the main elongate body 6103 z. In this embodiment, whenpressure or vacuum is supplied to the gap 6112, the braid layer 6109 canbe compressed by the bladder 6121 against the coil wound tube 6101 inthe main elongate body 6103 z and against the linkage sheath 6108 z inthe distal end section 6102 z to rigidize. The linkage sheath 6108 z issupported by the linkages 6104 z such that it can resist the pressure ofthe braid expanding. This design advantageously provides bothrigidization and linkages while maintaining a low wall thickness and/ordiameter. The distal end section 6102 z can, for example, include cables6124 extending within cable guides to activate the linkages 6104 z.

In some embodiments, the rigidizing structure can be steered from withinthe wall of the rigidizing structure and optionally without any links.FIG. 42B shows a cross section of a pressure rigidizing structure 2500where a cable guide 2599 is placed in the pressure gap 2512 and can beattached to the inner layer 2515. The cable 2524 extends from the cableguide 2599 into the distal end section 2502 z and is anchored to theinner layer 2515 at anchor point 2568. Pulling on the cable 2524 willcause the distal end section 2502 z (distal to the end of the cableguide 2599) to deflect. In some embodiments, the cable guide 2599 can beomitted, and the rigidizing device 2500 will bend along its entirelength when the cable 2524 is pulled. In some embodiments, the device2500 can be built with a distal end section 2502 z that has a lowerbending stiffness than the proximal elongate body 2503 z (as describedherein, for instance by varying the braid angle or using a more flexiblereinforcement element in either the inner or outer layer) so that thedistal end section 2502 z bends more than the body 2503 z. The cableguide 2599 and cables 2524 can be located between the bladder 2521 andthe braid 2509 or between the braid 2509 and outer layer 2501. The cableguide 2599 and/or the cables 2524 can be attached to the outer wall2501. Alternately, in a vacuum rigidized structure, the cable guide 2599and cables 2524 can be located between the inner layer and the braid orbetween the braid and the outer layer. In some embodiments, the bladder2521 and the braid of the braid layer 2509 can be omitted in the sectionwhere the cable 2524 is not inside the cable guide 2599, leaving onlyinner and outer layers 2515, 2501, or just an outer layer or just aninner layer.

Referring to FIGS. 43A-43C, in some embodiments, the distal end section4602 z can include active deflection segment 4646. The deflectionsegment 4646 can include a ribbon or spine extending therethrough thatprovides bending only in one or more predetermined directions uponactivation. The active deflection segment 4646 can be deflected, forexample, using one or more cables, bladders, pullwires, and/orintroduction of a guide wire, to a predetermined shape. The activedeflection segment 4646 can thus provide bending of the rigidizingdevice 4600 at a fixed location and in a fixed direction. In someembodiments, markers (e.g., radiopaque markers) can be positioned withinor proximate to the active deflection segment 4646 to indicate where thebend will occur and/or in which direction the active deflection segment4646 will bend. Bending of the rigidizing device 4600 using the activedeflection segment 4646 can be advantageous, for example, where bendingis required without assistance from the anatomy (i.e., when theanatomical path for the rigidizing device 4600 is not predefined orconstrained by the anatomy). For example, such bending might be usefulto create a bend across the open or relatively unconstrained spacebetween the inferior vena cava (IVC) and the atrial septum duringtransseptal procedures in the mitral valve. The active bending segment4646 can be configured to be rigidized (i.e., via pressure or vacuum) asdescribed herein to fix or lock the active deflection segment 4646 inthe bent configuration. Further, the rigidizing device 4600 can includea steerable distal section 4647 (e.g., with linkages) in addition to theactive deflection segment 4646. The steerable distal section 4647 can beused to point or orient the distal end of the rigidizing device 4646 inthe desired direction (e.g., via cables and/or along four axes), asdescribed elsewhere herein.

Any of the rigidizing devices described herein can include one or moreseparately rigidizing sections. For example, referring to FIGS. 44A-44C,in some embodiments, a rigidizing device 900 can have separatevacuum/pressure chambers 975 a-d (e.g., four vacuum or pressurechambers) along the length thereof. Each chambers 975 a,b,c,d can haveits own vacuum/pressure line 927 a-d extending thereto for individualrigidization of the chambers 975 a,b,c,d. Pressure seals 929 can extendbetween each chamber and/or at the distal end. The rigidizing device 900with separately rigidizing chambers 975 a,b,c,d can, in someembodiments, include a steerable distal section 902 z (e.g., withlinkages as otherwise described herein). The cables 924 a-d to controlthe steerable distal section 902 z can be managed using cable guides 999(e.g., there can be at least one, such as 1-4 cable guides 999 in eachvacuum chamber 975). In some embodiments, shown in FIG. 44B, the cables924 a-d, cable guides 999 a-d, and/or vacuum/pressure lines 927 a-d canextend within a radial gap 911 between the innermost layer 915 and thebraid layer 909 (and thus also beneath the outermost layer 901). Inother embodiments, shown in FIG. 44C, the cables 924 a-d, cable guides999 a-d, and/or vacuum/pressure lines 927 a-d can extend within thecentral lumen 920 of the rigidizing device 900. In use of the rigidizingdevice 900, any of the chambers 975 a-d that are in the flexible statecan be steered or deflected in the direction of cable tension while thechambers 975 a-d that are rigidized will remain in their position andnot be deflected. Advantageously, this design allows alternating whichchambers 975 a-d are under vacuum/pressure and/or direction of steeringto form a variety of complex shapes and provide navigation through theanatomy with minimal looping.

In some embodiments, the distal end section of the rigidizing devicesdescribed herein can include an element for local tissue stabilization,such as suction, a balloon or a cage element. For example, referring toFIGS. 45A-45D, in one embodiment, a rigidizing device 600 can include aballoon 666 and a balloon inflation lumen or tube 667 extending thereto.As shown in FIGS. 45B-45D (the outer layers have been removed in 6B-6Cfor clarity), the balloon inflation tube 667 can extend alongside theworking channel 655 (and thus within the radial gap 611 between the sliplayer 613 and the first braid layer 609). As shown in FIGS. 45B-45C, theinflation tube 667 can be configured to include a service loop 668 thatcan change lengths (i.e., straighten as in FIG. 45B or obtain a greaterbend as in 45C) to accommodate bending of the rigidizing device 600. Insome embodiments, the balloon inflation tube can be spiraled about itsaxis to accommodate bending. In some embodiments, a vacuum rigidizingdevice can include a balloon inflation tube between the innermost layerand the braid, between the braid and the outer layer, radially inwardsof the inner layer, or radially outwards of the outer layer. In someembodiments, a pressure rigidizing device can include an inflation lumenin the pressure gap, between the bladder and braid, between the braidand outer layer, radially inwards if the inner layer, or radiallyoutwards of the outer layer. For example, the inflation lumen can bepositioned similar to as described herein with respect to workingchannels and/or cables.

As another example, FIGS. 46A-46B show an exemplary vacuum tip 5354 foruse with a rigidizing device. The vacuum tip 5354 can include acircumferential array of vacuum holes 5358 on the distal-most face 5359.Further, the array of vacuum holes 5358 can be connected to a vacuumline 5356 that runs along the rigidizing device (e.g., within oralongside the layered walls of the rigidizing device). The vacuum line5356 can be connected to a source of vacuum such that, when activated,vacuum is provided through the vacuum line 5356 to each of the holes5358 of the array (e.g., through an annular inlet 5319 z). As a result,suction can be provided on the distal-most face 5359 of the tip 5354(and thus the distal-most face of the rigidizing device). Such suctioncan be useful, for example, to suction tissue thereto (e.g., forstabilization during interventional procedures such as for cannulationof the papilla, e.g., for access to the pancreatic duct or bile duct).The suction can also be useful, for example, for Endoscopic SubmucosaDissection (ESD), or Endoscopic Full Thickness Resection (EFTR).

In some embodiments, the vacuum tip 5354 can be positioned just distalto a steering section of the rigidizing device, which can advantageouslybe used to orient the vacuum tip 5354 in the desired direction. Further,in some embodiments, a tool (e.g., guidewire or scope) can pass throughthe central lumen 5320 z of the tip 5354 and between the array of vacuumholes 5358 to allow for procedures to be performed while suction isactivated.

Referring to FIGS. 47A-47B, in some embodiments, the vacuum tip 5254 caninclude a semi-annular array of holes 5238 at the distal-most face 5259rather than a circumferential array of holes.

Referring to FIGS. 48A-48B, in some embodiments, the vacuum tip 5454 canhave an angled distal face 5459 (e.g., angled at 30-80 degrees relativeto the longitudinal axis of the tip 5454, such as 30, 45, 60, 70, or 80degrees). The angled distal face can advantageously help approach angledanatomy to more easily adhere to the local surface.

The vacuum tips described herein can advantageously provide suctionwithout causing “red-out” of the endoscopic lens, as the suction canoccur locally (e.g., at the holes 5358) and not at the lens of thescope. Accordingly, the scope can provide visualization of the tissueeven when suction is applied.

In some embodiments, the vacuum tips described herein can include ametallized portion and/or have co-joined wires such that the vacuum tipscan conduct current. Such current can be used, for example, to cut orcoagulate the suctioned tissue.

In some embodiments, the vacuum tips described herein can be used with astandard endoscope or endoscopic type device that does not includerigidization.

Any of the rigidizing devices described herein can be used with a handleconfigured to allow manual manipulation and/or activation of the device.

An exemplary handle 1031 is shown in FIGS. 49A-49D. The handle 1031includes an activation element 1048 in the form of a button configuredto activate the vacuum or pressure (the button is shown off in FIGS. 49Aand 49C and on in FIGS. 49B and 49D). Further, a flow path within thehandle 1031 can include a vacuum or pressure inlet port 1049 configuredto be attached to the vacuum or pressure source, a rigidizing deviceport 1050 that connects to the rigidizing device via output 1073 z, anda vent port 1051 that connects to atmosphere. As shown in FIG. 49A, whenthe activation element 1048 is in a distal “off” position (i.e., suchthat vacuum or pressure for rigidization to the rigidizing device isoff), the vent port 1051 and rigidizing device port 1050 are incommunication with one another, thereby venting any rigidizing pressureor vacuum to the air and allowing the rigidizing device to be in aflexible configuration. As shown in FIG. 49B, when the activationelement 1048 is in a proximal “on” position (i.e., such that vacuum orpressure to the rigidizing device is on), the rigidizing device port1050 and the vacuum or pressure inlet port 1049 are in communicationwith one another, thereby supplying pressure or vacuum to the rigidizingdevice to allow the device to rigidize. In some embodiments, the handle1031 can be configured to be bonded to the rigidizing device (e.g., toan inner coil wound tube over the rigidizing device) at bonding region1053. As shown in FIGS. 49C-D, the handle includes a status indicatorelement 1067 z to indicate whether the rigidizing device is in theflexible or rigid configuration. In this embodiment, the statusindicator 1067 z is such that the word “on” shows when the button isplaced in the “on” position, and the word “off” shows when the button isplaced in the “off” position. In other embodiments, the status indicatorcan be a symbol, color, light, or moving indicator.

The activation element for a rigidizing device handle as describedherein can be a button, switch, toggle, slider, screwed connection,squeeze handle, or stop-cock. Further, the activation element can beplanar, a sector, or omnidirectional. The indicator element can includewords, lights, or an element that spins with flow of vacuum or pressure.For example, referring to FIGS. 50A-50B, in some embodiments, theactivation element 1548 can be a slider element. The activation element1548 can include a connection element 1574 z (e.g., a hollow tube orsnap-fit element) configured to slide over a handle. The indicatorelement 1567 z can be built into the slider (e.g., indicate “rigid” whenthe slider is in one position and “flexible” when the slider is inanother position). A similar slider actuation element 1648 (this oneorthogonal) can be seen in FIGS. 51A-51C.

In some embodiments, rather than including the activation element andindicator element on the handle, one or both can be on separateelements. For example, the activation element can be positioned alongthe vacuum or pressure line between the handle and the vacuum orpressure pump, can be actuated by a foot pedal, can be on the scopeumbilical, on the scope shaft, or can be clipped on the patient's bed.In some embodiments, the actuation element can be separate from thehandle, but can clip onto the handle during part of the procedure. Forexample, FIGS. 52A-52C show an activation element 1448 that includes anattachment mechanism 1452 (e.g., a c-shaped clip) for detachablecoupling to a handle 1431. Having the indicator element and/oractivation element separate from the handle can advantageously allow theactuator and indicator to be seen more clearly (i.e., not be obstructedby the person's anatomy) and/or can allow the actuator and indicator tobe controlled/used more easily by an additional person (e.g., aprocedural assistant).

FIGS. 53A-D show a handle 1131 that is designed to allow manipulation ofa rigidizing device, but that does not include an activation element oran indicator element. The handle 1131 includes a large stopper or flange1161 at the distal end thereof that can act as an insertion blocker forthe handle 1131 (i.e., to stop the handle 1131 from moving into theanatomy) and to act as a face against which the operator can push duringuse. The rigidizing device can connect at bond region 1153. Further, thehandle 1131 can include an input 1165 from the remote activation elementconnected to an output 1173 z to the rigidizing device.

In some embodiments, a handle for use with a vacuum rigidizing devicecan include a vent port to vent the rigidizing device when vacuum is notsupplied (i.e., when the rigidizing device is in the flexibleconfiguration). For example, FIGS. 54A-54B show a handle 1231 havingspool valve activation element 1248 that is shuttled in one direction toactivate the vacuum in the rigidizing device and can be shuttled in theopposite direction to deactivate the vacuum or pressure. Whendeactivating vacuum or pressure to the rigidizing device, the activationelement 1248 can provide venting via vent port 1251. The activationelement 1248 can be positioned on the vacuum or pressure line 1232leading to the handle, such as 4″-8″, e.g., 6″ away from the handle. Asshown in FIG. 54A, the spool valve with end button indicator element1267 z can indicate that the rigidizing device is in the flexibleconfiguration (as shown) or the rigid configuration (when pushed in theopposite direction).

Referring to FIGS. 55A-55C, the activation element 1348 can be a rotaryvalve (e.g., connected to the handle or elsewhere as described herein),and a sliding indicator 1367 z on the rotary valve activation element1348 can show that the vacuum or pressure is on (as shown in FIGS. 55Aand 55C) or off and vented (as shown in FIG. 55B).

In some embodiments, a handle for use with a vacuum rigidizing devicecan include a mechanism configured to automatically lock the handle inthe vacuum or vented configuration. For example, handle 7531 for usewith a vacuum rigidizing device 7500 is shown in FIGS. 56A-56G. Thehandle 7531 includes a handle body 7515 z configured to attach to therigidizing device 7500. The handle 7531 further includes an activationelement 7548 in the form of a switch ring for supplying vacuum to therigidizing device 7500. The switch ring activation element 7548 caninclude a magnet 7522 z that is configured to mate with either aproximal magnet 7523 z (as shown in FIG. 56D) or a distal magnet 7524 z(as shown in FIG. 56E). When the switch ring magnet 7522 z is mated withthe proximal magnet 7523 z, the vacuum feed line 7532 in the handle 7531is disconnected from the vacuum port 7550 to the rigidizing device, andboth the rigidizing device and the vacuum are vented or open to theatmosphere (as shown in FIG. 56F). When the switch ring magnet 7522 z ismated with the distal magnet 7523 z, the vacuum feed line 7532 in thehandle 7531 is connected to the vacuum port 7550 to the rigidizingdevice so as to supply vacuum thereto (as shown in FIG. 56G).Advantageously, the magnets 7522 z, 7523 z, 7524 z can lock the switchring 7548 in the vacuum or vent configurations, thereby preventing harmto the patient that could result if in the unintended configuration(e.g., attempted movement of the device 7500 through the anatomy when ina rigid configuration when it could damage the anatomy). In someembodiments, the magnet 7522 z can be a ferrous material while themagnets 7523 z, 7524 z can be magnets or vice versa. As shown in FIGS.56A-56B, the handle 7531 can further include a user grip 7521 z for theuser's hand with a grip cover 7525 z configured to cover the vacuum feedtube line 7532 in the handle 7531. Further, the vacuum feed tube line7532 can connect directly to the switch ring activation element 7548.The vacuum feed line 7532 may have a spiral or winding shape under thegrip cover 7525 z, which can allow the switch ring activation element7548 to move proximally and distally without restricted motion caused bythe vacuum feed line 7532. The spiraling of the vacuum feed line 7532may be from 30 to about 1440 degrees. For instance, 90 degrees (as shownin FIG. 56C where the grip cover is removed for clarity) 180, 360 and720 degrees. The grip cover 7525 z may be designed such that it coversthe whole vacuum feed line 7532 even when the spiral goes all the wayaround the handle 7531. The handle 7531 can further include a stopperflange 7561 to prevent the handle 7531 from moving into the anatomy (forinstance, the stopper flange may prevent the device from passing throughthe anus or through an oral bite guard), a proximal handle port 7526 zfor insertion of a scope or other working tool therethrough, and/or anindicator element 7567 z. The indicator element 7567 z is a band that isvisible only when the switch ring activation element 7548 is in thedistal position. The indicator element 7567 z may have a different colorand or value than the rest of the handle, preferably a color thatcontrasts sharply and is visible in reduced lighting configurations. Forinstance, the handle 7531 may be white and the indicator element 7567 zmay be a medium to dark blue. The indicator element 7567 z band may alsohave a different texture than the rest of the handle 7531. For instance,it may have raised bumps or a crosshatching. This may allow a physicianto easily feel the state of the handle 7531.

In some embodiments, a handle for use with a pressure rigidizing devicecan include a pressure gap inlet and a vent gap inlet. An exemplaryhandle 6231 attached to a pressure rigidizing device 6200 is shown inFIGS. 57A-57C. The handle includes a gap inlet 6293 and a vent gap inlet6223. Pressure gap inlet 6293 connects to pressure gap 6212 (viapressure line 6294). Vent gap inlet 6223 (which can extend all the waythrough the handle to exit on both sides thereof) connects to gap 6206around the braid layer 6209 (between the bladder 6221 and the outermostlayer 6201). The vent inlet 6223 can be open to atmosphere while the gapinlet 6293 can be connected to a pressure source (e.g., and activatedwith an activation element). The handle 6231 can, for example, be usedto operate the device 2200 g described with respect to FIG. 16G. In someembodiments, a fitting can be added to the gap inlet 6293 so that thehandle 6231 can be used to operate the device 2200 i as described withrespect to FIG. 16I.

In some embodiments, a handle for use with a pressure rigidizing devicecan include a pre-filled pressure medium therein. For example, anexemplary handle 7431 attached to a pressure rigidizing device 7400 isshown in FIGS. 58A-58E. The handle 7431 includes a handle body 7415 zand a grip/lever 7411 z that can be activated to provide pressure mediumto the rigidizing device 7400, such as pressure medium pre-filled orstored in the fluid chamber 7412 z of the handle 7431. The chamber 7412z can, for example, be bordered by a rolling diaphragm 7416 z. Thegrip/lever 7411 z can include teeth 7476 z that mate with a rack 7414 zof a piston 7413 z. As the grip/lever 7411 z is moved towards the handlebody 7415 z, the piston 7413 z can move distally towards the rollingdiaphragm 7416 z of the fluid chamber 7412 z. As the rolling diaphragm7416 z is pushed distally, it forces the pressure medium from thechamber 7412 z through the gap inlet 7493 to the pressure gap 7412outside of the bladder 7421 for stiffening (and air or other fluids canlikewise escape from around the braid layer via vent 7423). In someembodiments, the handle 7431 can include a locking mechanism (e.g., viaa click on/click off mechanism, such as that found in a ball point pen)with spring and feeler 7778 z configured to lock the grip/lever 7411 zagainst the body 7415 z so as to lock the rigidizing device 7400 in therigid configuration. Similarly, when the grip/lever 7411 z is pushedagainst the body again, the grip/lever 7411 can be released, and thefluid can move back into the fluid chamber 7412 z via inlet 7493.

In some embodiments, the handle 7431 can further include a pressurerelief valve 7417 z between the chamber 7412 z and an overflow chamber7418 z. When the pressure in the fluid chamber 7412 z reaches apredetermined maximum pressure (e.g., 5 atm), the pressure relief valve7417 z can open to allow fluid to be channeled into the overflow chamber7418 z. The fluid chamber 7412 z can be overfilled during manufacturingsuch that the valve 7417 always opens upon the first activation of thegrip/lever 7411 z, which can ensure calibration of the handle 7431 tothe desired pressure. One exemplary method of filling the fluid chamber7412 z can include: (1) attaching the handle 7431 to a filling fittingthat attaches to a tube leading to the pressure system; (2) drawing avacuum on the handle to remove air through that filling fitting; (3)while maintaining vacuum, introducing water, DI, Saline, an oil oranother incompressible fluid into the system through the fillingfitting; and (4) crimping and sealing the tube (via a mechanical crimp,via melting the tube, etc.) distal to the pressure fitting and thenremoving the pressure fitting, leaving the crimped/sealed tube in thehandle.

Any of the handles described herein can have a pressure indicatingfeature built in. For instance, the handles may have a pressure gauge.The handles may include a feature, such as a piston, that is displacedto give a visual indication that the device is pressurized. The handlesmay have a feature that flips or turns such that it displays a differentcolor; for instance, it may display a green dot at atmospheric pressureand red dot when rigidized. In some embodiments, the visual indicationcan be seen on fluoroscopy.

Any of the pressure rigidizing handles described may have an emergencyventing feature if, for some reason, the handle passageways becameclogged. The emergency venting feature can, for example, allow forincising of the device, thereby breaking its pressure cavity. Theemergency venting feature can, for example, be a valve distal to thehandle (for example, a swabable valve), such that should the valve beactuated, the device would vent pressure and therefore de-rigidize.

Any of the rigidizing devices described herein can include built-incameras, lighting, etc. to provide for on-board imaging. In someembodiments (and as shown below in FIG. 63), the cameras and lightingcan be positioned at the distal tip of the device. In other embodiments,and as shown in FIG. 59, a rigidizing device 8200 can include a camera8234 z and lighting 8235 z mounted on the elongate body 8203 z proximalto the distal end 8202 z of the device (e.g., proximal to steeringlinkages 8204 z).

In some embodiments, the rigidizing devices described herein can beconfigured as an introducer (i.e., an instrument for introduction of aflexible device, such as an introducer sheath for interventionalcardiology). For example, referring to FIG. 60, a rigidizing device 8700can include a rigidizing elongate body 8703 z with a tapered distal tip8733 z. The device 8700 can further include a hemostatic valve 8749 zand/or a flush line 8748 z.

The braid described herein can include or be replaced by a mesh, a wovenmaterial, a ribbon or a cloth. In some embodiments, the braid can benon-woven (i.e., fibers at different angles may not go over and undereach other but instead be on separate layers that do not cross eachother). Similarly, the braid can be replaced by a stent or a structure(e.g., metal structure) cut from a hypodermic tube.

In some embodiments, the rigidizing devices described herein can beconfigured to be loaded over the side of the scope or other instrument(e.g., rather than requiring insertion of the scope/instrument into theproximal end of the rigidizing device). For example, as shown in FIGS.61A-61B, the rigidizing device 400 can be split along the length thereof(i.e., split longitudinally through the wall from the proximal end tothe distal end). Further, a connection feature 444 can connect the splitwall together. In some embodiments, the connection feature 444 can bereusable. For example, the connection feature 444 can be a series ofmagnets that can engage (FIG. 61A) to hold the rigidizing device 400together and disengage (FIG. 61B) to provide side access for thescope/instrument. Other exemplary reusable connection features includezippers, interlocking zip-lock male and female configuration, orreusable tape. In some embodiments, the connection feature 444 can bepermanent and not reusable, such as permanent tape or adhesive.

In some embodiments, the vacuum and pressure multi-layered systemsdescribed herein can be used to create stiffness for non-cylindrical ornon-tubular structures. For example, the systems described herein couldbe used to create a balloon that assumes the desired shape whenpressurized and/or rigidized. Such a structure can be a flexiblestructure that nevertheless contains elements that exhibit high hoopstiffness, such as wire (tension or compression) or thin fiber strands(tension).

In some embodiments, the rigidizing devices described herein can includeproximal and distal seals within the innermost layer to create a spacebetween the scope or instrument and the innermost layer to holdlubrication.

In some embodiments, the rigidizing devices described herein can be usedin conjunction with other versions of the product. For example, anendoscope can include the rigidizing mechanisms described herein, and arigidizing device can include the rigidizing mechanisms describedherein. Used together, they can create a nested system that can advance,one after the other, allowing one of the elements to always remainstiffened, such that looping is reduced or eliminated (i.e., they cancreate a sequentially advancing nested system).

An exemplary nested system 2300 z is shown in FIG. 62. The system 2300 zcan include an outer rigidizing device 2300 and an inner rigidizingdevice 2310 (here, configured as a rigidizing scope) that are axiallymovable with respect to one another either concentrically ornon-concentrically. The outer rigidizing device 2300 and the innerrigidizing device 2310 can include any of the rigidizing features asdescribed herein. For example, the outer rigidizing device 2300 caninclude an outermost layer 2301 a, a braided layer 2309 a, and an innerlayer 2315 a including a coil wound therethrough. The outer rigidizingdevice 2300 can be, for example, configured to receive vacuum betweenthe outermost layer 2301 a and the inner layer 2315 a to providerigidization. Similarly, the inner scope 2310 can include an outer layer2301 b (e.g., with a coil wound therethrough), a braid layer 2309 b, abladder layer 2321 b, and an inner layer 2315 b (e.g., with a coil woundtherethrough). The inner scope 2310 can be, for example, configured toreceive pressure between the bladder 2321 b and the inner layer 2315 bto provide rigidization. Further, an air/water channel 2336 z and aworking channel 2355 can extend through the inner rigidizing device2310. Additionally, the inner rigidizing scope 2310 can include a distalsection 2302 z with a camera 2334 z, lights 2335 z, and steerablelinkages 2304 z. A cover 2327 z can extend over the distal section 2302z. In another embodiment, the camera and/or lighting can be delivered ina separate assembly (e.g., the camera and lighting can be bundledtogether in a catheter and delivered down the working channel 2355and/or an additional working channel to the distal-most end 2333 z).

An interface 2337 z can be positioned between the inner rigidizingdevice 2310 and the outer rigidizing device 2300. The interface 2337 zcan be a gap, for example, having a dimension d (see FIG. 62) of0.001″-0.050″, such as 0.0020″, 0.005″, or 0.020″ thick. In someembodiments, the interface 2337 z can be low friction and include, forexample, powder, coatings, or laminations to reduce the friction. Insome embodiments, there can be seals between the inner rigidizing device2310 and outer rigidizing device 2300, and the intervening space can bepressurized, for example, with fluid or water, to create a hydrostaticbearing. In other embodiments, there can be seals between the innerrigidizing device 2310 and outer rigidizing device 2300, and theintervening space can be filled with small spheres to reduce friction.

The inner rigidizing device 2310 and outer rigidizing device 2300 canmove relative to one another and alternately rigidize so as to transfera bend or shape down the length of the nested system 2300 z. Forexample, the inner device 2310 can be inserted into a lumen and bent orsteered into the desired shape. Pressure can be applied to the innerrigidizing device 2310 to cause the braid elements to engage and lockthe inner rigidizing device 2310 in the configuration. The rigidizingdevice (for instance, in a flexible state) 2300 can then be advancedover the rigid inner device 2310. When the outer rigidizing device 2300reaches the tip of the inner device 2310, vacuum can be applied to therigidizing device 2300 to cause the layers to engage and lock to fix theshape of the rigidizing device. The inner device 2310 can betransitioned to a flexible state, advanced, and the process repeated.Although the system 2300 z is described as including a rigidizing deviceand an inner device configured as a scope, it should be understood thatother configurations are possible. For example, the system might includetwo overtubes, two catheters, or a combination of overtube, catheter,and scope.

FIG. 63 shows another exemplary nested system 2700 z. System 2700 z issimilar to system 2300 z except that it includes a cover 2738 z attachedto both the inner and outer rigidizing device 2710, 2700. The cover 2738z may be, for example, low-durometer and thin-walled to allow elasticityand stretching. The cover 2738 z may be a rubber, such as urethane,latex, or silicone. The cover 2738 z may protect the interface/radialgap between the inner and outer devices 2710, 2700. The cover 2738 z mayprevent contamination from entering the space between the inner andouter tubes. The cover 2738 z may further prevent tissue and othersubstances from becoming trapped in the space between the inner andouter tubes. The cover 2738 z may stretch to allow the inner device 2710and outer device 2700 to travel independently of one another within theelastic limits of the material. The cover 2738 z may be bonded orattached to the rigidizing devices 2710, 2700 in such a way that thecover 2738 z is always at a minimum slightly stretched. This embodimentmay be wiped down externally for cleaning. In some embodiments, thecover 2738 z can be configured as a “rolling” seal, such as disclosed inU.S. Pat. No. 6,447,491, the entire disclosure of which is incorporatedby reference herein.

FIGS. 64A-64B show another exemplary nested system 9400 z. In thissystem 9400 z, the outer rigidizing device 9400 includes steering andimaging (e.g., similar to a scope) while the inner device includes onlyrigidization (though it could include additional steering elements asdescribed elsewhere herein). Thus, outer device 9400 includes linkagesor other steering means disclosed herein 9404 z, camera 9434 z, andlighting 9435 z. The outer device 9400 can further include a centralpassageway 9439 z for access to the inner device 9410 (e.g., lumens suchas working channels therein). In some embodiments, bellows or a loop oftubing can connect the passageway 9439 z to lumens of the inner device9410. Similar to the other nested systems, at least one of the devices9410, 9400 can be rigidized at a time while the other can conform to therigidization and/or move through the anatomy. Here, the outer device9400 can lead the inner device 9410 (the inner device 9410 is shownretracted relative to the outer device 9400 in FIG. 64A and extendedsubstantially even with the outer device 9400 in FIG. 64B).Advantageously, system 9400 z can provide a smooth exterior surface toavoid pinching the anatomy and/or entrance of fluid between the innerand outer devices 9410, 9400. Having the steering on the outer device9400 can also provide additional leverage for steering the tip. Also,the outer device can facilitate better imaging capabilities due to thelarger diameter of the outer device 9400 and its ability to accommodatea larger camera.

FIGS. 65A-65H show the exemplary use of a nested system 2400 z asdescribed herein. At FIG. 65A, the inner rigidizing device 2410 ispositioned within the outer rigidizing device 2400 such that the distalend of the inner rigidizing device 2410 extends outside of the outerrigidizing device 2400. At FIG. 65B, the distal end of the innerrigidizing device 2410 is bent in the desired direction/orientation andthen rigidized (e.g., using vacuum or pressure as described herein). AtFIG. 65C, the outer rigidizing device 2400 (in the flexibleconfiguration) is advanced over the rigidized inner rigidizing device2410 (including over the bending distal section). Once the distal end ofthe outer rigidizing device 2400 is sufficiently advanced over thedistal end of the inner rigidizing device 2410, then the outerrigidizing device 2400 can be rigidized (e.g., using vacuum or pressureas described herein). At FIG. 65D, the inner rigidizing device 2410 canthen be transitioned to the flexible state (e.g., by removing the vacuumor pressure as described herein and by allowing the steering cables togo slack such that tip can move easily) and can be advanced anddirected/oriented/steered as desired. Alternately, in FIG. 65D, theinner rigidizing device 2410 can be actively steered (either manually orvia computational control) as it emerges such that is minimizes the loadon the rigidized outer tube. Minimizing the load on the outer rigidizingdevice 2400 makes it easier for this tube to hold the rigidized shape.Once the inner rigidizing device 2410 is rigidized, the outer rigidizingdevice 2400 can be transitioned to the flexible state and advancedthereover (as shown in FIG. 65E). The process can then be repeated asshown in FIGS. 65F-H.

In some embodiments, at the completion of the sequence shown in FIGS.65A-H, a third rigidizing device can be slid over the first tworigidizing devices (2400, 2410) and rigidized. Rigidizing devices 2400and 2410 can then be withdrawn. Finally, a fourth rigidizing device canbe inserted through the inner lumen of the third tube. This fourthrigidizing device may have a larger diameter and more features thanrigidizing device 2410. For instance, it may have a larger workingchannel, more working channels, a better camera, or combinationsthereof. This technique can allow two smaller tubes, which tend to bemore flexible and maneuverable, to reach deep into the body while stillultimately deliver a larger tube for therapeutic purposes. Alternately,in the example above, the fourth rigidizing device can be a regularendoscope as is known in the art.

In some embodiments, at the completion of the sequence shown in FIGS.65A-H, outer rigidizing device 2400 may be rigidized and then the innerrigidizing device 2410 may be removed. For example, the rigidizingdevice 2410 may be a “navigation” device comprising a camera, lightingand a distal steering section. The “navigation” device 2410 may be wellsealed such that it is easy to clean between procedures. A second innerdevice may then be placed inside the rigidized outer device 2400 andadvanced past the distal end of the outer device 2400. The second innerdevice may be a “therapeutic” tube comprising such elements as a camera,lights, water, suction and various tools. The “therapeutic” device maynot have a steering section or the ability to rigidize, thereby givingadditional room in the body of the therapeutic tube for the inclusion ofother features, for example, tools for performing therapies. Once inplace, the tools on the “therapeutic” tube may be used to perform atherapy in the body, such as, for example, a mucosal resection ordissection in the human GI tract.

In another embodiment, after or during the completion of the sequenceshown in FIGS. 65A-H, a third device may be inserted inside inner tube2410. The third device may be rigidizing and/or an endoscope.

Although the outer rigidizing device for the nested systems describedherein is often referred to as rigidizing via vacuum and the inner scoperigidizing device as rigidizing via pressure, the opposite can be true(i.e., the outer rigidizing device can rigidize via pressure and theinner rigidizing device via vacuum) and/or both can have the samerigidizing source (pressure and/or vacuum).

Although the inner and outer elements of the nested systems aregenerally described as including integrated rigidizing elements, therigidizing elements can be separate (e.g., so as to allow relativesliding between the imaging scope elements and the rigidizing elements).

The rigidizing devices of the nested systems described herein can bedesigned such that inner rigidizing device can't rotate substantiallywithin outer rigidizing device when they are assembled. For instance,the outer surface of the inner rigidizing device can have longitudinalridges and grooves that form a spline. The inner surface of the outerrigidizing device can have corresponding ridges and grooves that matewith the same features in the outer rigidizing device.

Either or both of the rigidizing devices of the nested systems describedherein can be steerable. If both rigidizing devices are steerable, analgorithm can be implemented that steers whichever rigidizing device isflexible and moving longitudinally. The algorithm can steer the flexiblerigidizing device to anticipate the shape of the rigidized device thusminimizing the tendency for the moving, flexible rigidizing device tostraighten the rigid device.

If one rigidizing device of the nested systems described herein requiresvacuum and the other rigidizing device requires pressure, user controlscan be constructed in which moving one vs. the other (outer and inner)involves flipping a switch, with the switch toggling between a firstcondition in which, for example, one is pressurized for rigidity whenthe other is vented for flexibility and a second condition in which oneis vented for flexibility and the other is vacuumed for stiffness. This,for example, could be a foot pedal or a hand switch.

In some embodiments, the alternate movement of the nested systemsdescribed herein can be controlled manually. In other embodiments, thealternate movement can be controlled automatically, via a computerand/or with a motorized motion control system.

The nested systems described herein can advantageously be of similarstiffness. This can ensure that the total stiffnesses of the nestedsystem is relatively continuous. The nested systems described herein canbe small so as to fit in a variety of different anatomies. For example,for neurology applications, the outside diameter of the system can bebetween 0.05″-0.15″, such as approximately 0.1″. For cardiologyapplications, the outside diameter of the system can be between0.1″-0.3″, such as approximately 0.2″. For gastrointestinalapplications, the outside diameter of the system can be between0.3″-1.0″, such as 0.8″. Further, the nested systems described hereincan maintain high stiffness even at a small profile. For example, thechange in relative stiffness from the flexible configuration to therigid configuration can be multiples of 10×, 20×, 30×, and even larger.Additionally, the nested systems described herein can advantageouslymove smoothly relative to one another.

The nested systems described herein can advantageously navigate anarbitrary path, or an open, complex, or tortuous space, and create arange of free-standing complex shapes. The nested systems can furtheradvantageously provide shape propagation, allowing for shape memory tobe imparted from one element to another. In some embodiments,periodically, both tubes can be placed in a partially or fully flexiblestate such that, for instance, the radii or curvature of the systemincreases, and the surrounding anatomy provides support to the system.The pressure or vacuum being used to rigidize the tubes can be reducedor stopped to place the tubes in a partially or fully flexible state.This momentary relaxation (for instance, for 1-10 seconds) may allow thesystem to find a shape that more closely matches the anatomy it istravelling through. For instance, in the colon, this relaxation maygently open tight turns in the anatomy.

In some embodiments, the stiffness capabilities of the inner or outerrigidizing devices may be designed such that tight turns formed by theinner rigidizing device at its tip, when copied by the outer rigidizingdevice, are gradually opened up (made to have a larger radius) as theshape propagates proximally down the outer tube. For instance, the outerrigidizing device may be designed to have a higher minimum radius ofcurvature when rigidized.

The nested systems are continuous (i.e., non-segmented) and thereforprovide smooth and continuous movement through the body (e.g., theintestines). The nested systems can be disposable and low-cost.

In some embodiments, the outer rigidizing device can be a dynamicallyrigidizing overtube (e.g., as described in PCT/US18/42946, the entiretyof which is incorporated by reference herein). In some embodiments, theinner rigidizing device can be a rigidizing system or a commerciallyavailable scope, for example a 5 mm diameter nasal scope. Utilizingrigidization and a nested system enables the utilization of a smallerscope that delivers, compared to a duodenoscope, more flexibility ifdesired, more stiffness if desired, enhanced maneuverability, and theability to articulate at a much smaller radius of curvature.

In some embodiments, upon reaching the target destination, the innerrigidizing device of a nested system can be withdrawn. The outerrigidizing device can remain rigidized and contrast can be injectedthrough the inner element's space to fluoroscopically image.

RF coils can be used in any of the nested systems described herein toprovide a 3-D representation of whatever shape the nested system takes.That representation can be used to re-create a shape or return to agiven point (e.g., for reexamination by the doctor after an automatedcolonoscopy).

In some embodiments, the nested systems described herein can be usefulas a complete endoscope, with the internal structure carrying thepayload of working channels, pressurization lines, vacuum lines, tipwash, and electronics for lighting and imaging (vision systems,ultrasound, x-ray, MRI).

The nested systems described herein can be used, for example, forcolonoscopy. Such a colonoscopy nested system can reduce or eliminatelooping. It could eliminate the need for endoscopic reduction. Withoutlooping, the procedure can combine the speed and low cost of asigmoidoscopy with the efficacy of a colonoscopy. Additionally,colonoscopy nested systems can eliminate conscious sedation and itsassociated costs, time, risks, and facility requirements. Further,procedural skill can be markedly reduced for such colonoscopy proceduresby using the nested systems described herein. Further, in someembodiments, the nested systems described herein can provide automatedcolonoscopy, wherein a vision system automatically drives the nestedsystem down the center of the colon while looking for polyps. Such anautomated system would advantageously not require sedation nor a doctorfor the basic exam while allowing the doctor to follow up for furtherexamination if required.

In some embodiments, a rigidizing device as described herein can beconfigured as a rigidizing rod. Referring to FIG. 66, the rod 4900 caninclude an outer layer 4901, a braid layer 4909, and an inner bladderlayer 4921. Further, the gap 4912 within the bladder layer can be sealedand filled, for example, with air or water (e.g., to push the bladderlayer 4921 radially outwards). The outer layer 4901 can be awire-reinforced layer, such as a coil reinforced urethane tube. Thebraid layer 4901 can include braided strands 4933 and can include any ofthe features of other braid layers described herein. The inner bladderlayer 4921 can be made of a low durometer elastomer. The rod 4900 canfurther include an atraumatic tip that is soft and/or tapered.

In some embodiments, the distal end of the inner bladder layer 4921 canbe sealed to the outer layer 4901, and the rod 4900 can include an inletbetween the outer layer 4901 and the inner bladder layer 4921 to providevacuum for rigidization. In other embodiments, the distal end of theinner bladder layer 4921 can be sealed to itself or to the atraumaticdistal tip and the proximal end can be configured to have an inlet tothe inside of the inner bladder layer 4921 (i.e., radially inward of theinner bladder layer 4921) to provide pressure rigidization. Whenpressure rigidization is used, the rod 4900 can further include a venton the distal and/or proximal end to allow venting of air from betweenthe inner bladder layer 4921 and outer layer 4901 (thereby allowing thebladder 4921 to fully push the braid layer 4909 against the outer layer4901).

In some embodiments, the outer surface of the outer layer 4901 can becoated to provide a low friction surface including a hydrophiliccoating. In some embodiments, the outer diameter of the rod 4900 can beless than 5 mm, less than 4 mm, or less than 3 mm. For example, theouter diameter can be between 2 mm and 5 mm, such as between 2.5 mm and3 mm, such as approximately 2.8 mm. In some embodiments, an angle of thebraid of the braid layer 4909 can be less than 25 degrees relative to alongitudinal axis of the tube, such as approximately 5-15 degrees. Insome embodiments, there can be between 10 and 50 strands, such as 20-40strands, extending within the braid layer 4909.

Referring to FIG. 67, the rod 4900 can be used, for example, as astiffening wire for colonoscopy. In use as such, the colonoscope 5091can be inserted into the patient's colon. If looping occurs (therebyhindering advancement of the colonoscope), the scope 5091 can be left inplace, the working channel 5055 of the scope 5091 can be flushed, watercan be applied to the outer surface of the rod 4900 to activate thehydrophilic coating, and the rod 4900 can be inserted in the flexiblestate (i.e., un-rigidized) through the working channel 5055. Once therod 4900 is fully inserted into the endoscope such that the distal endof the rod 4900 is flush with the distal end of the colonoscope 5091vacuum or pressure can be applied to the rod 4900 (e.g., via pressureinlet and/or connector 5063 z), thereby rigidizing the rod. In someembodiments, the pressure or vacuum can be supplied to the rod 4900through a syringe or locking insufflator The colonoscope 5091 can beadvanced over the rod 4900 and relative to the patient while holding therod 4900 stationary relative to the patient. The vacuum or pressure canbe removed to advance or remove the rigidizing rod 4900.

Advantageously, the rod 4900 can thus be inserted into the scope 5091 ina flexible configuration so as to navigate around turns easily relativeto a standard stiffening wire (i.e., relative to a stiffening wire offixed rigidity). Further, the rod 4900 can conform to the shape of thelooped colon in the flexible configuration while providing a rigid trackfor the scope to ride along in the rigid configuration. Dynamictransitions of the rod 4900 between flexible and stiff configurationscan prevent unwanted straightening of the scope 5091 (which canotherwise occur with standard stiffening wires). Further, the atraumatictip of the rod 4900 can prevent damaging of the working channel 5055.The rigidizing rod 4900 can further be relatively long (e.g., longerthan the scope) without prohibiting navigation of the scope because thescope moves over and along the rigidizing rod 4900, and thus the rod4900 can work with a variety of scopes regardless of length of thescope. Similarly, the rod 4900 can have a diameter of 3.2 mm or less andcan thus work with a variety of endoscopes regardless of diameter (asmost endoscopes have a working channel that is 3.2 mm or larger).

The rigidizing systems and devices described herein can be used to treator access a number of different anatomical locations.

In one method of use, during a surgical procedure, a rigidizing deviceas described herein can be introduced to the patient in the flexibleconfiguration. Once the distal end of the rigidizing device ispositioned past the challenging anatomy (e.g., a portion of the anatomythat would cause looping or is otherwise difficult to pass with astandard instrument), the rigidizing device can be transitioned to therigid configuration. An instrument (e.g., a scope) can then be passedover or through the rigid device.

For example, the devices described herein can be used to navigate thegastrointestinal tract, to reach anatomical locations in the stomach,for abdominal access to anatomical locations otherwise blocked by otherorgans, for interventional endoscopic procedures (including ESD(Endoscopic Submucosal Dissection) and EMR (Endoscopic MucosalResection)), for direct cholangioscopy, for endoscopic retrogradecholangiopancreatography, for cardiac applications, for resection orsnaring of a lesion in the gastrointestinal tract, for enteroscopy, forEUS, to access the lungs, to access the kidneys, for neuro applications,for treatment of chronic total occlusions, for laparoscopic manualtools, for contralateral leg access, for ear nose and throatapplications, during esophagogastroduodenoscopy, for transoral roboticsurgery, for flexible robotic endoscopy, for natural orificetransluminal endoscopic surgery, or for altered anatomy cases. Specificexamples are further described below.

Further, the rigidizing devices described herein can have differentdimensions depending upon the desired application. For example, arigidizing device can have an inner diameter of approximately 0.3″-0.8″(e.g., 0.5″), an outer diameter of 0.4″-1.0″ (e.g., 0.6″), and a lengthof 50-200 cm, such as 75-150 cm, when designed, for example, for use inthe gastrointestinal tract. The rigidizing device can have an innerdiameter of, for example, 0.04″-0.3″ (e.g., 0.2″), an outer diameter of0.06″-0.4″, and a length of 30-130 cm when designed, for example, foruse in the cardiac vessels.

The rigidizing devices described herein can be used as overtubes forscopes in at least three different manners: (I) placement of theovertube after the scope has reached the destination; (II) overtubefollows the scope closely, but remains proximal to the tip of the scopeuntil the scope has reached its destination; or (III) the point andshoot method. An exemplary rigidizing device 2000 and scope 2091 isshown in FIGS. 68A-68B

For method I, the scope 2091 can be placed in the body at the desiredlocation using standard technique, and then the rigidizing device 2000can be advanced from the proximal end until the rigidizing device 2000is sufficiently supporting the scope 2091. For instance, in order toperform a resection in the colon, a doctor may advance a colonoscope tothe target site and then advance a rigidizing device almost orcompletely to the tip of the endoscope. The rigidizing device 2000 maythen be rigidized. The rigidized device 2000 can, for example,advantageously enhance control during resection of a colon by providinga stable surgical platform. The rigidized device 2000 can alsoadvantageously facilitate a good connection between the doctor's handmotion of the shaft of the scope 2091 external to the patient and motionof the tip of the scope 2091 (so called “1 to 1” motion).

For method II, the scope 2091 may lead the rigidizing device 2000 (forexample, the distal end of the scope 2091 and the distal end of therigidizing device 2000 may never approximately align) with therigidizing device repeatedly being switched between a flexible and rigidstate to aid advancement of the scope. For example, when advancing thescope 2091, the rigidizing device 2000 may be rigid, helping to preventscope looping and aiding in scope force transmission. Once the scope2091 has been advanced, the rigidizing device may be made flexible againand advanced distally on the scope. The process may be repeated.

Method III may include the following steps: (1) rigidizing device 2000can be in a flexible state with the distal end of the rigidizing device2000 approximately aligned with the distal end of the scope 2091; (2)scope 2091 can be steered with the distal end of the rigidizing device2000 positioned thereover and therefore being steered by the scope 2091;(3) rigidizing device 2000 can be placed in a rigid state that mirrorsthe steering position of the scope 2091; (4) the distal end of scope2091 can be advanced. This point and shoot method can advantageouslyallow the scope 2091 to be advanced in the direction to which the tip ofthe scope 2091 is pointing. In some embodiments, the steps can berepeated to advance the rigidizing device 2000 and scope 2091 within abody cavity or lumen.

It should be understood that methods I-III can be used in combinationwith one another. Further, in some embodiments, the rigidizing devicecan be steerable to further provide direction for the scope.

The three different manners of control can be used in the digestivetract. For example, these techniques may allow an endoscope 2691 a to bepositioned in the upper digestive tract 2646 z with a rigidizing device2600 a as shown in FIG. 69A. As another example, a rigidizing device2600 b may be used to position an endoscope 2691 b in the lowerdigestive tract 2647 z as shown in FIG. 69B. The described manners ofcontrol may make the positioning shown in FIGS. 69A and 69B easier andfaster to achieve, while minimizing risk of complications (such as GItract perforation) and reducing or eliminating patient discomfort formendoscopic looping.

The rigidizing devices and systems described herein can be used forendoscopic retrograde cholangiopancreatography (ERCP) and/or directcholangioscopy (DC). The goal of endoscopic retrogradecholangiopancreatography is to diagnose and treat disease in the bileand pancreatic ducts. This is most commonly performed with a sideviewing duodenoscope by navigating a guidewire into the bile andpancreatic ducts, injecting contrast into the ducts, viewing underfluoroscopy, and passing various tools through the ducts over the wire.It is desirable to directly visualize the ducts with a camera ratherthan using radiation and contrast injections. By passing a smallendoscope into the bile ducts, one can directly visualize the ductswithout radiation. However, it is very difficult to navigate such asmall endoscope through the stomach and into the bile duct as the scopewill tend to loop.

Cannulation of the bile or pancreatic duct is made difficult due to tworeasons. First, the endoscope must be small in order to fit inside thesmall ducts which means it is very flexible and buckles inside thestomach when trying to exit the stomach. Second, the duct entrance(papilla) is on the side of the duodenum wall which means the endoscopemust bend and advance at an angle relative to the long axis of theendoscope which cannot be done without a surface to deflect against. Therigidizing devices described herein can be used to create more optimalaccess and stabilization during ERCP and DC, including the kinematicallyand clinically challenging tasks of cannulating the papilla. Forexample, the devices described herein can be used both for getting tothe papilla (which is typically performed with a duodenoscope) and tocannulate the biliary and pancreatic trees.

Referring to FIGS. 70A-72D, the rigidizing devices described herein canbe used for ERCP and direct visualization of the pancreatic or bile duct(cholangioscopy) in a variety of ways. For example, as shown in FIGS.70A-70B, a rigidizing device 8300 (which can be similar to therigidizing device of FIG. 25) with a steerable distal end 8302 z may beused over a cholangioscope 8391. The cholangioscope 8391 can be aflexible endoscope with a camera, lighting, and optionally a toolchannel designed to achieve the bend radius and diameter necessary tonavigate into the bile ducts. The bend radius of the cholangioscope 8391can be 0.5″ with a distal tip and insertion tube diameter of 2 mm-6 mm.The cholangioscope 8391 can be placed inside the rigidizing device 8300,and the rigidizing device 8300 can begin in the flexible condition. Thetwo devices 8300, 8391 may be navigated together through the uppergastrointestinal tract to the duodenum 8354 z (or the cholangioscope8391 may be advanced ahead of the rigidizing device 8300 with therigidizing device 8300 following it when deemed necessary by theoperator). Once in the duodenum 8354 z, the rigidizing device 8300 canbe rigidized and steered to angle the cholangioscope 8391 towards theentrance to the ducts (papilla 8355 z). The rigidizing device 8300steering can be locked in place and the cholangioscope 8391 can beadvanced towards the papilla 8355 z. A guidewire 8385 can be pushedthrough the cholangioscope 8391 and aimed at the entrance to the papilla8355 z and pushed through into the bile duct 8357 z or the pancreaticduct 8356 z (positioning in the bile duct 8355 z is shown in FIG. 70A).As shown in FIG. 70B, the cholangioscope 8391 can be advanced into thebile duct 8357 z over the wire 8385 to achieve direct cannulation. Thisrigidizing device 8300 in this method can advantageously support thesmall cholangioscope 8391 to keep it from buckling in the stomach, andthe steering section 8302 z of the rigidizing device 8300 canadvantageously deflect the cholangioscope 8391 and direct it towards thepapilla. As a result, direct visualization can be achieved, reducing theamount of radiation required during ERCP.

Another exemplary ERCP method is shown in FIGS. 71A-71B. In thisembodiment, a rigidizing device 8400 without a steerable distal end canbe used. The cholangioscope 8491 can be used to steer the rigidizingdevice 8400 while in the flexible configuration to point the rigidizingdevice 8400 towards the papilla 8455 z. Once pointed in the correctdirection, the rigidizing device 8400 can be rigidized. Thecholangioscope 8491 can then be advanced in the same manner as describedabove with respect to FIGS. 70A-70B. This method can be referred to asthe “point and shoot” method of direct cholangioscopy.

Another exemplary ERCP method is shown in FIGS. 72A-72D. In thisembodiment, the rigidizing device 8500 includes at least two workingchannels therein (e.g., similar to the device of FIGS. 20A-20B and21A-21B). The cholangioscope 8591 is placed down the first tool channelinitially for navigation and cannulation of the papilla 8555 z. Once theguidewire 8585 has been crossed into the bile duct 8557 z (as shown inFIG. 72B) or pancreatic duct (8556 z), the cholangioscope 8591 can beremoved from the first tool channel with the wire 8585 remaining inplace inside the duct 8557 z (as shown in FIG. 72C). The cholangioscope8591 can then be placed into the second tool channel (e.g., which mayextend sideways out of the wall of the device 8500 as shown in FIG. 81)such that the duodenal side of the papilla 8555 z can be seen (as shownin FIG. 72D). The first tool channel can be used to place largerinstruments therethrough, such as a stent 8558 z to be placed into theduct 8557 z. In some embodiments, it may be useful to have to haveexterior (duodenal) visualization of the papilla 8555 z during stentplacement since the stent 8558 z takes up most of the diameter of theduct 8557 z and a portion of the stent 8558 z remains inside theduodenum 8554 z.

In another exemplary ERCP method, a rigidizing device similar to thedevice of FIG. 59 includes a single tool channel running the entirelength of the device. The rigidizing device includes a camera attachedto the outside of the rigidizing device just proximal to the steeringsection. Cannulation, ERCP, and direct cholangioscopy can be performedsimilar to the methods described above. When a stent or larger tools areto be used, the cholangioscope can be removed from the tool channel andthe rigidizing device camera can be used to view the exterior of thepapilla while larger instruments or stents are used.

In another exemplary ERCP method, the rigidizing device includes asuction tip on the distal end thereof as described in FIGS. 46A-46B. Thesuction tip can surround the papilla, and suction can be applied at thetip. This action can stabilize the papilla and make it easier for thecholangioscope to aim to the appropriate location to cross the wire.Holding the surrounding tissue of the papilla can also provide somecounter-tension when pushing on the papilla with the wire orcholangioscope. Providing counter tension to the compression force ofthe cholangioscope or other tools could decrease the number ofsphincterotomies (cutting open the papilla) required.

Advantageously, the rigidizing devices used for ERCP as described hereincan be disposable and sterile, reducing risk of infection orcross-patient contamination. The methods further result in lessradiation and easy of navigation to the papilla with steeringcapabilities on the rigidizing device and/or the scope.

The rigidizing devices and systems described herein can be used forcardiology and cardiac surgery, including in the aortic and mitralvalves.

Typically, in transcatheter, percutaneous procedures, the clinicianaffects motion from the access site (e.g., an artery or vein in thegroin, arm, etc.) using some sort of flexible rod or shaft that hasadequate stiffness to advance the catheter to the treatment site but isflexible enough to conform to the anatomy. This means that all the forceor leverage is developed at the remote access site and may be reflectedoff of more local anatomy to: (a) bend the flexible rod or shaft tonavigate to the procedure site; and to (b) provide localized forces(linear and torque) at the procedure site. In contrast, a dynamicallyrigidizing device as described herein effectively moves the access siteto the treatment site by providing a means to both navigate throughtortuous anatomy to the treatment site and to rigidize and form a stableport at the treatment site independent of anatomical reflections.

One of the advantages of the rigidizing devices described herein is theability to conform to surrounding anatomy (e.g., the vasculature).Devices such as guide catheters need to provide a certain amount ofstiffness to be advanced through the anatomy (e.g. vasculature) andperform the functions required. Stiff systems, however, can prevent thedevice from being advanced to the target anatomy due, at least in part,to highly tortuous paths, forcing the anatomy to conform to the device,which can lead to trauma to surrounding tissues and vessels. Incontrast, the rigidizing devices described herein can be flexible enoughto be moved through the vasculature, conforming to the vasculatureinstead of remodeling the vasculature. The inch-worming allowed by arigidizing device or nested system as described herein allows for thisflexible forward movement. Once the device has advanced to a targetsite, the rigidization allows for preservation and utilization of thecreated path through the vasculature. The rigidizing devices describedherein, for example, can be 1/10 as stiff as a typical guide catheterwhen in a flexible state and 5 times stiffer than a typical guidecatheter when in a rigid state.

In some embodiments, a rigidizing device as described herein can be usedduring percutaneous procedures in the heart or vasculature. Therigidizing device can both conform to the cardiac anatomy and provide alocal distal fulcrum for instrument manipulation. Currently, whenperforming a percutaneous procedure, the mechanical fixation andstabilization occurs at the access site (e.g., femoral vein, radialartery, iliac vein, etc.). As described above, this fixation pointcreates a long moment arm extending from the access site to theprocedure site. Further, as described in further detail below, themechanical linkage created by typical stiff catheter systems between theaccess site and target anatomy relies on anatomical reflections todirect the catheter tip and transmit force to the tools being used.Stiff catheter systems create potential energy along the access routewhen they are bent to conform to the anatomy. This energy can bereleased when there is voluntary or involuntary patient movement orunintentional movement by the operator at the access site. In contrast,the rigidizing devices described herein conform to the anatomicalpathway prior to rigidization, eliminating stored energy associated withstiff catheter systems. Once rigidized, the mechanical fixation isachieved independently of anatomical reflections, greatly reducing themoment arm and increasing a physician's control over the procedure toolsleading to more predictable results. In some embodiments, the rigidizingdevice can comprise an integrated hemostasis valve, obviating the needfor a separate access sheath.

In some embodiments, the rigidizing devices described herein can be usedto stiffen a guide sheath in interventional cardiology or structuralheart cases. For example, the rigidizing devices can be used to providea “rail” for the transcatheter aortic valve replacement (TAVR) device,thereby keeping the tip of the TAVR catheter from scraping and skivingthe top of the aortic arch where there is often thrombus burden (currentsystems tend to ride the outside of the arch, rubbing against plaques,creating embolic debris). The rigidizing devices can help enablesuperior alignment and placement as well as lower paravalvular leakageand optimal placement relative to pacing nodes.

In some embodiments, the rigidizing devices described herein can be usedas a delivery system that may be passed from the venous circulationthrough the right atrium and atrial septum into the left atrium throughthe mitral valve and antegrade into the left ventricular outflow tractand aortic valve. In this manner, a transcatheter aortic valveimplantation (TAVI) may be facilitated avoiding contact with the aorticarch and ascending aorta typical with retrograde deployment

In some embodiments, the rigidizing devices described herein can be usedto deliver a mitral valve replacement. That is, crossing the septal wallduring mitral valve replacement can be particularly difficult, as itinvolves multiple curves, a beating heart, and the need for preciselyaligned entry and stabilization before delivery of the implant. Currentvalve delivery platforms can be quite rigid, which can be dangerous foranatomy that it straightens (such as the femoral artery, which can behighly calcified and friable). The rigidizing devices described hereincan advantageously create a conduit that goes in flexibly, thenrigidizes in whatever shape the particular person's anatomy provided,such that the rigidizing device conforms to the entire anatomical track.As a result, the rigidizing devices described herein can allow theclinician to create a stable mechanical lumen leading directly to theanatomy, to locate it without significant local anatomical load, then tostabilize rigidly in that shape as a device is delivered through it.

FIG. 73A depicts an embodiment of a rigidizing device 3700 advancedthrough the right atrium RA to the left atrium of the heart. A guidewireor other piercing member and dilator can be used to puncture the atrialseptum 3704 to create access to the left atrium LA. The rigidizingdevice 3700 can be advanced to the treatment site using the methodsdescribed herein. A cardiac tool 3787 (which may or may not berigidizing) can be advanced within with the rigidizing device 3700. Forexample, the cardiac tool 3787 and rigidizing device 3700 can beadvanced as described with respect to the nested system shown herein,such as in FIGS. 65A-H. The dynamic nature of the rigidization allowsthe device 3700 and tool 3787 to be advanced through tortuous anatomy.The rigidizing device 3700 can be rigidized once at the treatment siteto provide a stable base for the treatment. Optionally, the rigidizingdevice 3700 may comprise an anchoring balloon 3778 near its distal tipto anchor the rigidizing device 3700 to chambers in the heart, e.g., tothe atrial septum 3704 to maintain the tip of the tube 3700 in the leftatrium LA. The detailed view of FIG. 73B shows the balloon 3778. Theballoon 3778 can be positioned at any location around a circumference ofthe tube 3700. In some embodiments, the balloon is annular and surroundsa circumference of the tube 3700. The rigidizing device 3700 may includean echogenic tip. Other tips allowing real time visualization are alsopossible (e.g., radiographic tip, a scope within a saline filled bag,etc.).

FIGS. 74A-74B show an exemplary method for use of a dynamicallyrigidizing device in performing treatment of a in a small branchingvessel, such as the coronary arteries. When navigating to these smallervessels, oftentimes, applying force in these areas can cause the guidecatheter or other advanced devices to be pushed out of the area.Sometimes, access sheaths are used in such situations to provide a bitof mechanical advantage. Still, using such an access sheath, whenapplying force, for example, to push through an occlusion, the wholedevice can be pushed out of the area. FIG. 74A-74B compare the use of astandard guide catheter to a rigidizing device as described herein. InFIG. 74A, a standard guide catheter 3886 is used to navigate to theostium 3845 of one of the main coronary arteries 3842. A guidewire 3885extends from the tip of the guide catheter 3886 and can be used toperform a procedure (e.g., placing a stent). The guide catheter 3886can, in some embodiments, reflect off of adjacent anatomy 3873 toachieve mechanical advantage, prevent catheter push back, and/or providemore local force. In contrast, FIG. 74B show a rigidizing device 3800 asdescribed herein advanced through the ostium 3845 and into the coronaryartery 3842. Because of the rigidization capability of the device 3800,it does not need to reflect off local anatomy and can instead provideinherent stabilization at the treatment site. Additionally, because ofthe dynamic rigidization capabilities of the rigidizing device, it canbe advanced past the ostium 3845 and into the coronary artery 3842.

FIG. 75A shows an exemplary method of using a dynamically rigidizingovertube system for performing a mitral valve repair. This methodillustrates how the rigidizing device 3900 can be positioned in the leftatrium LA such that it independently maintains axial alignment with thetreatment site, in this example, the mitral valve. As shown in FIG. 75A,the rigidizing device 3900 is advanced through the vasculature to theright atrium RA, through the atrial septum, and into the left atrium LA.The end of the rigidizing device can be steered such that a longitudinalaxis 3983 extending through the end 3969 of the tube aligns with thedesired treatment area (e.g., portion of the valve). The steering,dynamically rigidizing, and tip visualization capabilities can allow forprecise positioning of the rigidizing device. For example, the axis 3983extends through the mitral valve MV into the left ventricle LV. Anotherposition 3964 of the rigidizing device 3900 is shown in phantom with theaxis extending through a leaflet of the mitral valve MV. Current methodsof mitral valve repair utilize a guide catheter to navigate to the leftatrium LA, and often reliable axial alignment is not possible. Thepresently disclosed method of using the rigidizing device 3900 toachieve axial alignment in a flexible state prior to rigidizationprovides a significant benefit over currently used methods ofpositioning during procedures such as mitral valve repair. This sort ofprecise alignment can be beneficial in other areas of the anatomy aswell (e.g., across other valves, in transseptal access sites, within avessel lumen, etc.), including the ability to place sutures, clips andother devices within the heart with equivalent precision normallyreserved for open heart surgery.

Referring to FIG. 75B, the rigidizing device 3900 used in a proceduresuch as that shown in FIG. 75A can comprise various configurations. Insome embodiments, the rigidizing device 3900 can be steered andpositioned using a guidewire 3985. In some embodiments, the rigidizingdevice 3900 can comprise a nested system comprising an inner rigidizingdevice 3910.

As shown in FIG. 75C, in one embodiment, at needle-tipped catheter 3958z can be advanced through the rigidizing device 3900 and positionedwithin the cardiac anatomy, such as above a mitral valve leaflet. Insome embodiments, the needle-tipped catheter 3958 z can contain ananchoring device 3962 z (pledget, stainless steel pledget, etc.)attached to a length of suture 3959 z that can be passed through thetissue creating an anchor for the suture. Suture and anchors deliveredthrough the rigidizing device can be used to sew tissue structurestogether, such as leaflet plication for mitral valve repair.

It will be appreciated that a system comprising one or more rigidizingdevices as described herein can be used in heart procedures other thanmitral valve repair. For example, the system may be used in complexmitral valve procedures where the goal may be to effect leaflet repairand mitral annuloplasty during the same procedure. The system can beused to perform transseptal delivery of an aortic prosthesis (e.g.,TAVI). In some embodiments, the system is used to perform aortic valverepair via transseptal access. A combination of dynamically rigidizingovertubes can used in synchrony to pass suture or other instruments fromone heart chamber to another. In any of these procedures, thedynamically rigidizing systems described herein can advantageouslyprovide a cannula or access sheath providing universal access to thevarious chambers of the heart.

FIG. 76A shows an exemplary dual rigidizing cannula system that can besimultaneously placed in multiple chambers of the heart. The tworigidizing cannulas 4000 a, 4000 b can be axially aligned and providethe capability for clinicians to pass instruments from one cannula tothe other. In use, the first rigidizing cannula 4000 a can be navigatedthrough the right atrium RA to the left atrium LA with the tip 4004 ofthe cannula facing towards the mitral valve 4081. The rigidizing cannula4000 a can be rigidized in this position. The cannula 4004 a maycomprise a bending section near the tip 4004 to properly position thetip and steer the device. The second cannula 4000 b can be navigatedretrograde through the aorta 4066 z into the left ventricle LV. Thecannula 4000 b can be steered and positioned such that a tip 4039 ispositioned below the mitral valve and facing the tip 40004 of the firstcannula 4000 a. The cannula 4000 b can be rigidized in this position.The axis 4014 extending between the tip 4004 of the first cannula andthe tip 4039 of the second cannula can be aligned with the area to betreated. This dual access can allow, for example, a suture to be passedfrom one cannula to the other and/or to allow tools to be passedtherebetween. Using two cannulas can also allow the procedure to beperformed with a greater degree of precision and accuracy (for example,the treatment site can be approached from the top, or bottom, or both).Examples of procedures that can be performed with two such rigidizingcannulas 4000 a, 400 b include leaflet plication with standard suturetechniques and annuloplasty with conventional rings. Each cannula 4000a, 4000 b can include multiple working channels and provide fixed accesssites within the heart. The provision of these dual fixation sites canallow for replication of standard open heart surgical procedures throughfar less invasive percutaneous access.

FIG. 76B shows the dual rigidizing cannula system of FIG. 76A being usedto pass suture through a tissue. The first rigidizing device 4000 a ispositioned on a first side of tissue 4061 z to be sutured. The secondrigidizing device 4000 b is positioned on an opposite side of the tissue4061 z. A needle catheter 4058 z positioned by the first device 4000 acan be used in combination with a tool 4065 z such as a grasper, snare,or the like positioned by the second device 4000 b to pass suturethrough the tissue 4061 z.

Referring to FIG. 77, in some embodiments, a rigidizing device asdescribed herein can be used as a trocar during endoscopic procedures.FIG. 77 shows a dynamically rigidizing trocar 4141 and a standard trocar4138. Typically, when using a standard trocar 4138, the initialplacement of the trocar 4138 can be incorrect, requiring removal andrepositioning. In contrast, the dynamically rigidizing trocar 4141 canallow for minor adjustments during or after placement of the trocar. Thedynamically rigidizing trocar 4141 can have steering capability, asdescribed with respect to other dynamically rigidizing devices disclosedherein. Using this capability, the trocar 4141 can be bent or deflectedin a desired direction and then rigidized, allowing far greater controlthan standard trocars. The dynamically rigidizing trocar 4141 can beused in cardiac applications and/or elsewhere in the body. Additionally,the trocar 4141 can be provided in different sizes or shapes dependingon the application.

Referring to FIG. 78, a dynamically rigidizing device 4200 can be usedat the aortic bifurcation 4297. This area of the vasculature cancommonly become diseased and require complex repair based on the extremetortuous anatomy at this site. Currently, many catheters or otherdelivery devices used to treat this area travel up to the apex of thebifurcation and then deploy tools down from there. As shown in FIG. 78,a dynamically rigidizing device 4200 can use a combination of steeringand dynamic (e.g., periodic) rigidization to navigate around thebifurcation 4297 and be able to reach any treatment site in the area.For example, the system shown in FIG. 78 can be used to treat a CTO(chronic total occlusion) in one leg by making percutaneous access inthe other leg.

Referring to FIG. 79, a rigidizing device 4700 with an active deflectionsegment 4746 and a steerable distal section 4747 can be used in theheart to perform mitral valve repair. The rigidizing device 4700 can bepositioned in the left atrium LA such that it independently maintainsaxial alignment with the treatment site, in this example, the mitralvalve MV. The rigidizing device 4700 can thus be advanced through thevasculature to the right atrium RA, through the atrial septum, and intothe left atrium LA. The end of the rigidizing device can be steered suchthat a longitudinal axis 4783 extending through the end 4769 of the tubealigns with the desired treatment area (e.g., portion of the valve). Toachieve the desired positioning, the active deflection segment 4746 canbe bent in the relatively unconstrained space between the IVC and theatrial septum while the distal steerable section 4747 can be positionedwithin the left atrium LA and steered or oriented towards the mitralvalve MV. In such a position, the rigidizing device 4700 can have a bendwith an arc radius of approximately 4-6 cm, such as 5 cm, at an angle of90 degrees or more.

Referring to FIG. 80, a rigidizing device 4800 for use in mitral valverepair (with active deflection segment 4846 and steerable distal section4847) can include a distal payload 4848 (e.g., a mitral clip, mitralvalve replacement, or annuloplasty ring) attached thereto. Having thedistal payload 4848 attached thereto while still incorporating theactive deflection segment 4846 and steerable distal section 4847 canadvantageously reduce or eliminate the need for an outer large-boreguide catheter during such procedures. The catheter 4800 (or 4700) foruse in mitral valve procedures can, for example, be 14-40 Fr with alength of 80-120 cm.

A method of using the rigidizing device 4700 or 4800 can include: (1)introducing the device into the distal circulation; (2) advancing thedevice to the target anatomy (e.g. heart valve); (3) making a first bendwith the active deflection segment (e.g., negotiating the bend betweenthe IVC and septal wall, which is approximately 90°); (4) locking theactive deflection segment in the bent configuration using pressure orvacuum; and (5) using the steerable distal section to get to the mitralplane and mitral valve; and (6) delivering a therapy or payload.

A rigidizing device with an active deflection section and a steerabledistal section as described herein can also be used, for example, forplacement of fenestrated grafts for thoracic artery or for abdominalaneurysm repair that involves critical branch vessels that requiretreatment.

The rigidizing devices and systems described herein can be used forresection or snaring of a lesion in the gastrointestinal tract.

Referring to FIGS. 81A-81F, in some embodiments, the rigidizing device700 can be configured so as to control the directionality of a workingtool 777 that extends through the working channel 755. For example, therigidizing device 700 can include a flexible distal section 702 z thatis highly flexible relative to the proximal rigidizing elongate body 703z (which can include rigidizing features as described herein) extendingproximally thereof. Referring to FIG. 81A, the endoscope 791 with ascope steering section 776 can be placed within the rigidizing device700 in vessel 760 z. Referring to FIG. 81B, the rigidizing device 700can be moved distally such that the flexible distal section 702 z ispositioned over the steering section 776 of the endoscope 791. As shownin FIG. 81C, as the steering section 776 bends, the flexible distalsection 702 z and the connected working channel 755 can bend with it,thereby providing steering of the tool 777 in the working channel 755(e.g., towards the lesion 779 in the vessel 736). As shown in FIG. 81D,the tool 777 can then be advanced out of the working channel 755 to thedesired location (e.g., the lesion 779). Referring to FIG. 81E, therigidizing device 700 can then be pulled proximally to move the flexibledistal portion 702 z off of the steerable section 776 and to move theworking channel 755 further proximally as well. As shown in FIG. 81F,this can allow the scope 791 to be steered (with the steerable section776) without disturbing the placement or direction of the working tool777.

The rigidizing devices and systems described herein can be used forenteroscopy to navigate substantially all of the small intestine todiagnose and/or treat disease.

Enteroscopy is kinematically challenging for several reasons, includingbecause the scopes are relatively small diameter (9 mm), they are verylong (2 meters), and they frequently loop as they navigate thegastrointestinal tract to get to the beginning or end of the smallintestine (the pylorus or the ileocecal valve, respectively).

The rigidizing devices and systems described herein can be used forIEUS.

The rigidizing devices and systems described herein can be used toaccess the lungs. For example, a rigidizing device 2100 and a scope 2191can be assembled concentrically (the scope inside the rigidizing device)and then placed through the mouth down the trachea to the carina. Asdetailed herein, a “Point and Shoot” method may be employed at thecarina to advance the scope into the left main or right main bronchus.The “Point and Shoot” method may be repeatedly used to selectadditional, deeper branches in the lungs.

The rigidizing devices and systems described herein can be used toaccess the kidneys. For example, a rigidizing device 2100 and a scope2191 can be assembled concentrically (the scope inside the rigidizingdevice) and then placed through the urethra into the bladder. Asdetailed herein, a “Point and Shoot” method may be employed in thebladder to advance the scope into the left or right ureter. The “Pointand Shoot” method may be repeatedly used to help the scope reach thekidneys

The rigidizing devices and systems described herein can be used tonavigate through neurological anatomy.

Systems described herein may be used to access the carotid arteries orthe distal vessels leading to or in the brain.

For example, a guidewire may be placed into the carotid artery. Arigidizing device or sheath may be placed over the guidewire anddirected into the carotid artery. Once the overtube or sheath is placedat the target site, it may be rigidized to decrease the likelihood ofthe catheter or guidewire prolapsing into the aortic arch during theprocedure.

The rigidizing devices and systems described herein can be used foraccess and/or treatment of chronic total occlusions (CTO).

Thus, in some embodiments, the rigidizing devices can be incorporatedinto catheters for interventional cardiology, such that they track veryeasily (flexible), then can be rigidized for instances when the deviceis used to push through locally anatomy, such as for instance whentreating a CTO.

The rigidizing devices and systems described herein can be used withlaparoscopic manual tools.

The rigidizing devices and systems described herein can be used forcontralateral leg access.

The rigidizing devices and systems described herein can be used for ear,nose, and throat (ENT) applications.

The rigidizing devices and systems described herein can be used toperform therapies during esophagogastroduodenoscopy (EGD), for example,on the roof of the stomach.

The rigidizing devices and systems described herein can be used for TORS(transoral robotic surgery).

The rigidizing devices and systems described herein can be used forNOTES (Natural Orifice Transluminal Endoscopic Surgery).

The rigidizing devices and systems described herein can be used foraltered anatomy cases, including Roux-en-Y.

It should be understood that any feature described herein with respectto one embodiment can be combined with or substituted for any featuredescribed herein with respect to another embodiment. For example, thevarious layers and/or features of the rigidizing devices describedherein can be combined, substituted, and/or rearranged relative to otherlayers.

Additional details pertinent to the present invention, includingmaterials and manufacturing techniques, may be employed as within thelevel of those with skill in the relevant art. The same may hold truewith respect to method-based aspects of the invention in terms ofadditional acts commonly or logically employed. Also, it is contemplatedthat any optional feature of the inventive variations described may beset forth and claimed independently, or in combination with any one ormore of the features described herein. Likewise, reference to a singularitem, includes the possibility that there are a plurality of the sameitems present. More specifically, as used herein and in the appendedclaims, the singular forms “a,” “and,” “said,” and “the” include pluralreferents unless the context clearly dictates otherwise. It is furthernoted that the claims may be drafted to exclude any optional element. Assuch, this statement is intended to serve as antecedent basis for use ofsuch exclusive terminology as “solely,” “only” and the like inconnection with the recitation of claim elements, or use of a “negative”limitation. Unless defined otherwise herein, all technical andscientific terms used herein have the same meaning as commonlyunderstood by one of ordinary skill in the art to which this inventionbelongs. The breadth of the present invention is not to be limited bythe subject specification, but rather only by the plain meaning of theclaim terms employed.

When a feature or element is herein referred to as being “on” anotherfeature or element, it can be directly on the other feature or elementor intervening features and/or elements may also be present. Incontrast, when a feature or element is referred to as being “directlyon” another feature or element, there are no intervening features orelements present. It will also be understood that, when a feature orelement is referred to as being “connected”, “attached” or “coupled” toanother feature or element, it can be directly connected, attached orcoupled to the other feature or element or intervening features orelements may be present. In contrast, when a feature or element isreferred to as being “directly connected”, “directly attached” or“directly coupled” to another feature or element, there are nointervening features or elements present. Although described or shownwith respect to one embodiment, the features and elements so describedor shown can apply to other embodiments. It will also be appreciated bythose of skill in the art that references to a structure or feature thatis disposed “adjacent” another feature may have portions that overlap orunderlie the adjacent feature.

Terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention.For example, as used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, steps, operations, elements, components, and/orgroups thereof. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items and may beabbreviated as “/”.

Spatially relative terms, such as “under”, “below”, “lower”, “over”,“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if a device in thefigures is inverted, elements described as “under” or “beneath” otherelements or features would then be oriented “over” the other elements orfeatures. Thus, the exemplary term “under” can encompass both anorientation of over and under. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly. Similarly, the terms“upwardly”, “downwardly”, “vertical”, “horizontal” and the like are usedherein for the purpose of explanation only unless specifically indicatedotherwise.

Although the terms “first” and “second” may be used herein to describevarious features/elements, these features/elements should not be limitedby these terms, unless the context indicates otherwise. These terms maybe used to distinguish one feature/element from another feature/element.Thus, a first feature/element discussed below could be termed a secondfeature/element, and similarly, a second feature/element discussed belowcould be termed a first feature/element without departing from theteachings of the present invention.

As used herein in the specification and claims, including as used in theexamples and unless otherwise expressly specified, all numbers may beread as if prefaced by the word “about” or “approximately,” even if theterm does not expressly appear. The phrase “about” or “approximately”may be used when describing magnitude and/or position to indicate thatthe value and/or position described is within a reasonable expectedrange of values and/or positions. For example, a numeric value may havea value that is +/−0.1% of the stated value (or range of values), +/−1%of the stated value (or range of values), +/−2% of the stated value (orrange of values), +/−5% of the stated value (or range of values), +/−10%of the stated value (or range of values), etc. Any numerical rangerecited herein is intended to include all sub-ranges subsumed therein.

What is claimed is:
 1. A rigidizing device comprising: an elongateflexible tube; a braid layer positioned over the elongate flexible tube,the braid layer having a plurality of strands braided together at abraid angle of 5-40 degrees relative to a longitudinal axis of theelongate flexible tube when the elongate flexible tube is straight; anouter layer over the elongate flexible tube and the braid layer; aninlet between the elongate flexible tube and the outer layer andconfigured to attach to a source of vacuum or pressure; and a sealedchannel between the elongate flexible tube and the outer layer, thesealed channel comprising a working channel, a cable guide, or aninflation lumen; wherein the rigidizing device is configured to have arigid configuration when vacuum or pressure is applied through the inletand a flexible configuration when vacuum or pressure is not appliedthrough the inlet; and wherein the braid angle is configured to changeas the rigidizing device bends when the rigidizing device is in theflexible condition.
 2. The rigidizing device of claim 1, wherein therigidizing device in the rigid configuration is at least two timesstiffer than the rigidizing device in the flexible configuration.
 3. Therigidizing device of claim 1, wherein the elongate flexible tubecomprises a reinforcement element extending therein.
 4. The rigidizingdevice of claim 1, wherein the plurality of strands are braided togetherat 4-60 picks per inch.
 5. The rigidizing device of claim 1, wherein theplurality of stands comprise polyethylene terephthalate or stainlesssteel.
 6. The rigidizing device of claim 1, wherein the braid layerprovides a coverage of 30-70% relative to the elongate flexible tube. 7.The rigidizing device of claim 1, wherein the inlet is configured toattach to a source of pressure, and wherein the rigidizing devicefurther comprises a bladder layer therein, the bladder layer configuredto be pushed against the braid layer when pressure is supplied throughthe inlet.
 8. The rigidizing device of claim 1, wherein the outer layerfurther comprises a plurality of reinforcement elements therein.
 9. Therigidizing device of claim 1, wherein the inlet is configured to attachto a source of vacuum, and wherein the outer layer is a thin flexiblesheath.
 10. The rigidizing device of claim 1, further comprising aradial gap between the braid layer and the outer layer, the gap having athickness of 0.00002″-0.04″.
 11. The rigidizing device of claim 1,further comprising a steerable distal end.
 12. A rigidizing devicecomprising: an elongate flexible tube; a braid layer positioned over theelongate flexible tube; an outer layer over the elongate flexible tubeand the braid layer; an inlet between the elongate flexible tube and theouter layer and configured to attach to a source of vacuum or pressure;and a sealed channel between the elongate flexible tube and the outerlayer, the sealed channel comprising a working channel, a cable guide,or an inflation lumen; wherein the rigidizing device is configured tohave a rigid configuration when vacuum or pressure is applied throughthe inlet and a flexible configuration when vacuum or pressure is notapplied through the inlet, and where a ratio of stiffness of therigidizing device in the rigid configuration to stiffness of therigidizing device in the flexible configuration is greater than
 5. 13.The rigidizing device of claim 12, wherein the ratio is greater than 10.14. The rigidizing device of claim 12, wherein the elongate flexibletube comprises a reinforcement element extending therein.
 15. Therigidizing device of claim 12, wherein the braid layer comprises aplurality of strands braided together, the plurality of standscomprising polyethylene terephthalate or stainless steel.
 16. Therigidizing device of claim 12, wherein the inlet is configured to attachto a source of pressure, and wherein the rigidizing device furthercomprises a bladder layer therein, the bladder layer configured to bepushed against the braid layer when pressure is supplied through theinlet.
 17. The rigidizing device of claim 12, wherein the outer layerfurther comprises a plurality of reinforcement elements therein.
 18. Therigidizing device of claim 12, wherein the inlet is configured to attachto a source of vacuum, and wherein the outer layer is a thin flexiblesheath.
 19. The rigidizing device of claim 12, further comprising asteerable distal end.
 20. A rigidizing device comprising: an elongateflexible tube; a braid layer positioned radially outwards of theelongate flexible tube; a slip layer adjacent to the braid layer; anouter layer over the elongate flexible tube, the braid layer, and theslip layer; and a vacuum or pressure inlet between the elongate flexibletube and the outer layer and configured to attach to a source of vacuumor pressure; wherein the rigidizing device is configured to have a rigidconfiguration when vacuum or pressure is applied through the inlet and aflexible configuration when vacuum or pressure is not applied throughthe inlet; and wherein the slip layer is configured to reduce frictionbetween the braid layer and the elongate flexible tube or the outerlayer when the rigidizing device is in the flexible configuration. 21.The rigidizing device of claim 20, wherein the slip layer has a lowercoefficient of friction than the braid layer.
 22. The rigidizing deviceof claim 20, wherein the slip layer comprises a powder.
 23. Therigidizing device of claim 20, wherein the elongate flexible tubecomprises a reinforcement element extending therein.
 24. The rigidizingdevice of claim 20, wherein the braid layer comprises a plurality ofstrands braided together, the plurality of stands comprisingpolyethylene terephthalate or stainless steel.
 25. The rigidizing deviceof claim 20, wherein the inlet is configured to attach to a source ofpressure, and wherein the rigidizing device further comprises a bladderlayer therein, the bladder layer configured to be pushed against thebraid layer when pressure is supplied through the inlet.
 26. Therigidizing device of claim 20, wherein the outer layer further comprisesa plurality of reinforcement elements therein.
 27. The rigidizing deviceof claim 20, wherein the inlet is configured to attach to a source ofvacuum, and wherein the outer layer is a thin flexible sheath.
 28. Therigidizing device of claim 20, further comprising a steerable distalend.
 29. A rigidizing device comprising: an elongate flexible tube; abraid layer positioned over the elongate flexible tube, the braid layerhaving a plurality of strands braided together at a braid angle of 5-40degrees relative to a longitudinal axis of the elongate flexible tubewhen the elongate flexible tube is straight; an outer layer over theelongate flexible tube and the braid layer; an inlet between theelongate flexible tube and the outer layer and configured to attach to asource of pressure; and a bladder layer, the bladder layer configured tobe pushed against the braid layer when pressure is supplied through theinlet; wherein the rigidizing device is configured to have a rigidconfiguration when pressure is applied through the inlet and a flexibleconfiguration when pressure is not applied through the inlet; andwherein the braid angle is configured to change as the rigidizing devicebends when the rigidizing device is in the flexible configuration. 30.The rigidizing device of claim 29, wherein the rigidizing device in therigid configuration is at least two times stiffer than the rigidizingdevice in the flexible configuration.
 31. The rigidizing device of claim29, wherein the elongate flexible tube comprises a reinforcement elementextending therein.
 32. The rigidizing device of claim 29, wherein theplurality of strands are braided together at 4-60 picks per inch. 33.The rigidizing device of claim 29, wherein the plurality of standscomprise polyethylene terephthalate or stainless steel.
 34. Therigidizing device of claim 29, wherein the braid layer provides acoverage of 30-70% relative to the elongate flexible tube.
 35. Therigidizing device of claim 29, wherein the outer layer further comprisesa plurality of reinforcement elements therein.
 36. The rigidizing deviceof claim 29, further comprising a radial gap between the braid layer andthe outer layer, the gap having a thickness of 0.00002″-0.04″.
 37. Therigidizing device of claim 29, further comprising a steerable distalend.
 38. A rigidizing device comprising: an elongate flexible tube; abraid layer positioned over the elongate flexible tube; an outer layerover the elongate flexible tube and the braid layer; an inlet betweenthe elongate flexible tube and the outer layer and configured to attachto a source of pressure; and a bladder layer, the bladder layerconfigured to be pushed against the braid layer when pressure issupplied through the inlet; wherein the rigidizing device is configuredto have a rigid configuration when pressure is applied through the inletand a flexible configuration when pressure is not applied through theinlet, and where a ratio of stiffness of the rigidizing device in therigid configuration to stiffness of the rigidizing device in theflexible configuration is greater than
 5. 39. The rigidizing device ofclaim 38, wherein the ratio is greater than
 10. 40. The rigidizingdevice of claim 38, wherein the elongate flexible tube comprises areinforcement element extending therein.
 41. The rigidizing device ofclaim 38, wherein the braid layer comprises a plurality of strandsbraided together, the plurality of stands comprising polyethyleneterephthalate or stainless steel.
 42. The rigidizing device of claim 38,wherein the outer layer further comprises a plurality of reinforcementelements therein.
 43. The rigidizing device of claim 38, furthercomprising a steerable distal end.